SERIES 2005-1 SUPPLEMENTAL INDENTURE

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Exhibit 4.1

SERIES 2005-1
SUPPLEMENTAL INDENTURE OF TRUST

by and between

GCO EDUCATION LOAN FUNDING TRUST-I

and

ZIONS FIRST NATIONAL BANK,
as Indenture Trustee

Authorizing the Issuance of:

$500,000,000
GCO Education Loan Funding Trust-I
GCO ELF Student Loan Asset-Backed Notes
Series 2005-1

Dated as of March 1, 2005

Table of Contents

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SERIES 2005-1 SUPPLEMENTAL INDENTURE OF TRUST

         THIS SERIES 2005-1 SUPPLEMENTAL INDENTURE OF TRUST (this "Supplemental Indenture"), dated as of March 1, 2005, is by and between GCO EDUCATION LOAN FUNDING TRUST-I , a Delaware statutory trust (the "Issuer"), and ZIONS FIRST NATIONAL BANK , a national banking association (together with its successors, the "Indenture Trustee"), as Indenture Trustee hereunder (all capitalized terms used in these preambles, recitals and granting clauses shall have the same meanings assigned thereto in Article I hereof);

W I T N E S S E T H:

        WHEREAS, the Issuer has previously entered into an Indenture of Trust, dated as of March 1, 2003 (the "Indenture"), among the Issuer, the Indenture Trustee and Zions First National Bank, as Eligible Lender Trustee, as amended and supplemented by a Series 2003-1 Supplemental Indenture of Trust, dated as of March 1, 2003 (the "Series 2003-1 Supplemental Indenture"), between the Issuer and the Indenture Trustee, a Series 2003-2 Supplemental Indenture of Trust, dated as of September 1, 2003 (the "Series 2003-2 Supplemental Indenture"), between the Issuer and the Indenture Trustee and a Third Supplemental Indenture, dated as of December 1, 2004 (the "Third Supplemental Indenture"), between the Issuer and the Indenture Trustee; and

        WHEREAS, the Issuer desires to enter into this Supplemental Indenture in order to issue Notes pursuant to the terms of the Indenture, including Section 2.09 thereof; and

        WHEREAS, the Issuer represents that it is duly created as a statutory trust under the laws of the State of Delaware and that by proper action it has duly authorized the issuance of $500,000,000 of its GCO ELF Student Loan Asset-Backed Notes, Series 2005-1, consisting of three classes designated as Senior Class 2005-1 (the "Class A Notes") and one class designated as Subordinate Class 2005-1 (the "Class B Notes" and together with the Class A Notes, the "Series 2005-1 Notes"), and it has by proper action authorized the execution and delivery of this Supplemental Indenture; and

        WHEREAS, the Series 2005-1 Notes constitute Notes as defined in the Indenture; and

        WHEREAS, the Indenture Trustee has agreed to accept the trusts herein created upon the terms herein set forth;

        NOW, THEREFORE, it is mutually covenanted and agreed as follows:

ARTICLE I
DEFINITIONS AND USE OF PHRASES

        All words and phrases defined in the Indenture shall have the same meaning in this Supplemental Indenture, except as otherwise appears in this Article. In addition, the following terms have the following meanings in this Supplemental Indenture unless the context clearly requires otherwise:

        " Auction Rate Securities " means, collectively, the Class A-6AR Notes and the Class B Notes.

        " Authorized Denominations " means (a) for purposes of the LIBOR Rate Notes, $5,000 and any integral multiple of $1,000; and (b) for the purposes of the Auction Rate Securities, the definition of "Authorized Denominations" set forth in Appendix A hereto.

        " Business Day " means (a) for purposes of the LIBOR Rate Notes, (i) for purposes of calculating LIBOR, any day on which banks in New York, New York and London, England are open for the transaction of international business and (ii) for all other purposes, any day other than a Saturday, Sunday, holiday or other day on which the New York Stock Exchange or banks located in New York, New York or the city in which the principal office of the Indenture Trustee is located are authorized or permitted by law or executive order to close; and (b) for purposes of the Auction Rate Securities, the definition of "Business Day" set forth in Appendix A hereto.

        " Class A Notes " means, collectively, the Class A-2L Notes, the Class A-3L Notes and the Class A-6AR Notes.

        " Class A-1L Notes " means the $100,000,000 GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2003-2, Senior Class A-1L LIBOR Floating Rate issued pursuant to the Series 2003-2 Supplemental Indenture.

        " Class A-2L Notes " means the $140,000,000 GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2005-1, Senior Class A-2L LIBOR Floating Rate.

        " Class A-3L Notes " means the $235,000,000 GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2005-1, Senior Class A-3L LIBOR Floating Rate.

        " Class A-6AR Notes " means the $100,000,000 GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2005-1, Senior Class A-6AR Auction Rate Securities.

        " Class B Notes " means the $25,000,000 GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2005-1, Subordinate Class B-3AR Auction Rate Securities.

        " Closing Date " means, with respect to the Series 2005-1 Notes, March 15, 2005.

        " Ending Balance Factor " means, with respect to a class of the LIBOR Rate Notes, for any given day, the number calculated by dividing the unpaid principal balance of the Outstanding LIBOR Rate Notes of such class (after any Principal Reduction Payments are made), by the original principal balance of the LIBOR Rate Notes of such class, and rounding the result to nine decimal places.

        " Interest Accrual Period " means, with respect to the LIBOR Rate Notes, initially, the period commencing on the Closing Date, to but not including May 25, 2005, and thereafter, with respect to each Quarterly Distribution Date, the period beginning on the prior Quarterly Distribution Date and ending on the day immediately preceding such Quarterly Distribution Date.

        " LIBOR " means, with respect to any Interest Accrual Period, the London interbank offered rate for deposits in U.S. dollars having a maturity of three months which appears on Telerate Page 3750 as of 11:00 a.m., London time, on the related LIBOR Determination Date as determined by the Indenture Trustee or its agent. If this rate does not appear on Telerate Page 3750, the rate for that day will be determined on the basis of the rates at which deposits in U.S. dollars, having a maturity of three months and in a principal amount of not less than U.S. $1,000,000, are offered at approximately 11:00 a.m., London time, on that LIBOR Determination Date, to prime banks in the London interbank market by the Reference Banks. The Indenture Trustee will request the principal London office of each Reference Bank identified to it by the Administrator to provide a quotation of its rate. If the Reference Banks provide at least two quotations, the rate for that day will be the arithmetic mean of the quotations. If the Reference Banks provide fewer than two quotations, the rate for that day will be the arithmetic mean of the rates quoted by major banks in New York City, selected by the Administrator at approximately 11:00 a.m., New York time, on that LIBOR Determination Date, for loans in U.S. dollars to leading European banks having a maturity of three months and in a principal amount of not less than U.S. $1,000,000. If the banks selected as described above are not providing quotations, the LIBOR in effect for the applicable Interest Accrual Period will be the LIBOR in effect for the previous Interest Accrual Period.

        " LIBOR Determination Date " means, for each Interest Accrual Period for the LIBOR Rate Notes, the second Business Day before the beginning of that Interest Accrual Period.

        " LIBOR Rate Notes " means, collectively, the Class A-2L Notes, and the Class A-3L Notes.

        " Principal Reduction Payment " means, with respect to a class of the LIBOR Rate Notes, a payment of principal on such class of the LIBOR Rate Notes prior to the Stated Maturity thereof.

        " Principal Reduction Payment Date " means each Quarterly Distribution Date on which a Principal Reduction Payment is made with respect to a class of the LIBOR Rate Notes.

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        " Quarterly Distribution Date " means the 25th day of February, May, August and November, or, if such day is not a Business Day, the immediately succeeding Business Day, commencing on May 25, 2005.

        " Redemption Account " means the Redemption Account established within the Acquisition Fund pursuant to the Series 2003-1 Supplemental Indenture and Section 3.01 hereof.

        " Reference Banks " means, with respect to a determination of LIBOR for any Interest Accrual Period by the Indenture Trustee, four major banks in the London interbank market selected by the Administrator.

        " Regular Record Date " means (a) for purposes of the LIBOR Rate Notes, the Business Day prior to the Quarterly Distribution Date and (b) for the purposes of the Auction Rate Securities, the "Regular Record Date" set forth in Appendix A hereto.

        " Reserve Fund Requirement " means 1.00% of the aggregate amount of the Series 2005-1 Notes Outstanding; provided, however, that so long as any Series 2005-1 Notes remain Outstanding there shall be at least $500,000 on deposit in the Reserve Fund. Further, such percentages and amounts may be changed upon satisfaction of the Rating Agency Condition and receipt of a Rating Confirmation.

        " Series 2003-1 Notes " means the GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2003-1 issued pursuant to the Series 2003-1 Supplemental Indenture in the aggregate principal amount of $220,000,000.

        " Series 2003-1 Supplemental Indenture " means the Series 2003-1 Supplemental Indenture of Trust, dated as of March 1, 2003, between the Issuer and the Indenture Trustee.

        " Series 2003-2 Notes " means the GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2003-2 issued pursuant to the Series 2003-2 Supplemental Indenture in the aggregate principal amount of $200,000,000.

        " Series 2003-2 Supplemental Indenture " means the Series 2003-2 Supplemental Indenture of Trust, dated as of September 1, 2003, between the Issuer and the Indenture Trustee.

        " Series 2005-1 Acquisition Account " means the Series 2005-1 Acquisition Account established within the Acquisition Fund pursuant to Section 3.01 hereof.

         "Series 2005-1 Counterparty" means Citibank, N.A.

        " Series 2005-1 Derivative Product Agreements " means, collectively, the ISDA Master Agreement (including the schedule thereto), between the Issuer and the Series 2005-1 Counterparty.

        " Series 2005-1 Notes " means the GCO Education Loan Funding Trust-I, GCO ELF Student Loan Asset-Backed Notes, Series 2005-1 issued pursuant to this Supplemental Indenture in the aggregate principal amount of $500,000,000 consisting of the Class A Notes and the Class B Notes.

        " Targeted Amortization Schedule " means, with respect to a class of the LIBOR Rate Notes, the Schedule set forth as Appendix B to this Supplemental Indenture for Principal Reduction Payments on such class of the LIBOR Rate Notes prior to Stated Maturity thereof to the extent moneys are available for such purpose in the Redemption Account of the Acquisition Fund.

        " Telerate Page 3750 " means the display page so designated on the Telerate Service (or such other page as may replace that page on that service for the purpose of displaying comparable rates or prices).

        " Third Supplemental Indenture " means the Third Supplemental Indenture of Trust, dated as of December 1, 2004, between the Issuer and the Indenture Trustee.

        Words importing the masculine gender include the feminine gender. Words importing persons include firms, associations and corporations. Words importing the singular number include the plural

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number and vice versa. Additional terms are defined in the body of this Supplemental Indenture and the Appendices hereto.

        In the event that any term or provision contained herein with respect to the Series 2005-1 Notes shall conflict with or be inconsistent with any term or provision contained in the Indenture, the terms and provisions of this Supplemental Indenture shall govern.

ARTICLE II
SERIES 2005-1 NOTE DETAILS,
FORMS OF SERIES 2005-1 NOTES,
REDEMPTION OF SERIES 2005-1 NOTES
AND USE OF PROCEEDS OF SERIES 2005-1 NOTES

        Section 2.01. Series 2005-1 Note Details.     The aggregate principal amount of the Series 2005-1 Notes which may be initially authenticated and delivered under this Supplemental Indenture is limited to, and shall be individually issued in four separate classes consisting of $140,000,000 of Class A-2L Notes, $235,000,000 of Class A-3L Notes, $100,000,000 of Class A-6AR Notes, and $25,000,000 of Class B Notes, except for Series 2005-1 Notes authenticated and delivered upon transfer of, or in exchange for, or in lieu of Notes pursuant to Sections 2.03 and 2.04 of the Indenture. The Series 2005-1 Notes shall be issuable only as fully registered notes in the Authorized Denominations. The Series 2005-1 Notes of each class shall each be lettered "R" and shall be numbered separately from 1 upwards, respectively. The Class A-2L Notes, the Class A-3L Notes and the Class A-6AR Notes constitute Senior Notes. The Class B Notes constitute Subordinate Notes. The Series 2005-1 Derivative Product Agreements constitute Senior Obligations.

        The Class A-2L Notes, the Class A-3L Notes (collectively, the "LIBOR Rate Notes") shall be dated their Closing Date and shall bear interest from their Closing Date, payable on each Quarterly Distribution Date, except that LIBOR Rate Notes which are reissued upon transfer, exchange or other replacement shall bear interest from the most recent Quarterly Distribution Date to which interest has been paid, or if no interest has been paid, from the Closing Date. The Class A-2L Notes shall bear interest for each Interest Accrual Period, other than the first Interest Accrual Period, at a per annum rate equal to LIBOR, plus 0.03%. The interest rate on the Class A-2L Notes for the first Interest Accrual Period shall be 2.99%. The Class A-3L Notes shall bear interest for each Interest Accrual Period, other than the first Interest Accrual Period, at a per annum rate equal to LIBOR, plus 0.08%. The interest rate on the Class A-3L Notes for the first Interest Accrual Period shall be 3.04%. Interest payable on the LIBOR Rate Notes shall be computed on the assumption that each year contains 360 days and actual days elapsed and rounding the resultant figure to the fifth decimal place. The Class A-2L Notes shall mature, subject to Principal Reduction Payments, on August 25, 2014 (the Class A-2L Notes' "Stated Maturity"). The Class A-3L Notes shall mature, subject to Principal Reduction Payments, on November 25, 2020 (the Class A-3L Notes' "Stated Maturity").

        The Class A-6AR Notes and Class B Notes (collectively, the "Auction Rate Securities") shall be dated their Closing Date and shall bear interest from their Closing Date, payable on each Payment Date (as defined in Appendix A to this Supplemental Indenture), except that Auction Rate Securities which are reissued upon transfer, exchange or other replacement shall bear interest from the most recent Payment Date to which interest has been paid, or if no interest has been paid, from the Closing Date. The Auction Rate Securities shall mature on March 25, 2042 (the Class A-6AR and Class B Notes' "Stated Maturity"). The terms of and definitions related to the Auction Rate Securities are found in Article I hereof and Appendix A to this Supplemental Indenture.

        The principal of the Series 2005-1 Notes due at Stated Maturity or redemption in whole shall be payable at the Corporate Trust Office of the Indenture Trustee, or such other location as directed by the Indenture Trustee, or at the principal office of its successor in trust upon presentation and

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surrender of the Series 2005-1 Notes. Payment of interest and principal paid subject to a redemption on any Series 2005-1 Note shall be made to the Noteholder thereof by check or draft mailed on the Payment Date by the Indenture Trustee to the Noteholder at his address as it last appears on the registration books kept by the Indenture Trustee at the close of business on the Regular Record Date for such Payment Date, but any such interest not so timely paid or duly provided for shall cease to be payable to the Noteholder thereof at the close of business on the Regular Record Date and shall be payable to the Noteholder thereof at the close of business on a special record date (a "Special Record Date") for the payment of any such defaulted interest. Such Special Record Date shall be fixed by the Indenture Trustee whenever moneys become available for payment of the defaulted interest, and notice of such Special Record Date shall be given to the Noteholders of the Series 2005-1 Notes not less than 10 days prior thereto by first-class mail to each such Noteholder as shown on the Indenture Trustee's registration books on the date selected by the Indenture Trustee, stating the date of the Special Record Date and the date fixed for the payment of such defaulted interest. Payment of interest to the Securities Depository or its nominee shall, and at the written request addressed to the Indenture Trustee of any other Noteholder owning at least $1,000,000 principal amount of the Series 2005-1 Notes, payments of interest shall, be paid by wire transfer within the United States to the bank account number filed no later than the Regular Record Date or Special Record Date with the Indenture Trustee for such purpose. All payments on the Series 2005-1 Notes shall be made in lawful money of the United States of America.

•         (a)   Except as otherwise provided in this Section, the Series 2005-1 Notes in the form of one global note for each Stated Maturity date shall be registered in the name of the Securities Depository or its nominee and ownership thereof shall be maintained in book-entry form by the Securities Depository for the account of the Agent Members. Initially, each Series 2005-1 Note shall be registered in the name of CEDE & CO., as the nominee of The Depository Trust Company. Except as provided in subsection (d) of this Section, the Series 2005-1 Notes may be transferred, in whole but not in part, only to the Securities Depository or a nominee of the Securities Depository or to a successor Securities Depository selected or approved by the Issuer or to a nominee of such successor Securities Depository. Each global note shall bear a legend substantially to the following effect: "Except as otherwise provided in the Indenture, this global note may be transferred, in whole but not in part, only to another nominee of the Securities Depository, as defined in the Indenture, or to a successor Securities Depository or to a nominee of a successor Securities Depository."

          (b)   Except as otherwise provided herein, the Issuer and the Indenture Trustee shall have no responsibility or obligation with respect to (i) the accuracy of the records of the Securities Depository or any Agent Member with respect to any beneficial ownership interest in the Series 2005-1 Notes; (ii) the delivery to any Agent Member, beneficial owner of the Series 2005-1 Notes or other Person, other than the Securities Depository, of any notice with respect to the Series 2005-1 Notes; or (iii) the payment to any Agent Member, beneficial owner of the Series 2005-1 Notes or other Person, other than the Securities Depository, of any amount with respect to the principal of or interest on the Series 2005-1 Notes. So long as the certificates for the Series 2005-1 Notes issued under this Supplemental Indenture are not issued pursuant to paragraph (c) of this Section the Issuer and the Indenture Trustee may treat the Securities Depository as, and deem the Securities Depository to be, the absolute owner of the Series 2005-1 Notes for all purposes whatsoever, including, without limitation, (A) the payment of principal of and interest on such Series 2005-1 Notes, (B) giving notices of redemption and other matters with respect to such Series 2005-1 Notes, and (C) registering transfers with respect to such Series 2005-1 Notes. In connection with any notice or other communication to be provided to the Noteholders pursuant to this Supplemental Indenture by the Issuer or the Indenture Trustee with respect to any consent or other action to be taken by the Noteholders, the Issuer or the Indenture Trustee, as the case may be, shall establish a record date for such consent or other action and, if

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• the Securities Depository shall hold all of the Series 2005-1 Notes, give the Securities Depository notice of such record date not less than 15 calendar days in advance of such record date to the extent possible. Such notice to the Securities Depository shall be given only when the Securities Depository is the sole Noteholder.

          (c)   If at any time the Securities Depository notifies the Issuer and the Indenture Trustee that it is unwilling or unable to continue as Securities Depository with respect to any or all of the Series 2005-1 Notes or if at any time the Securities Depository shall no longer be registered or in good standing under the Securities Exchange Act or other applicable statute or regulation and a successor Securities Depository is not appointed by the Issuer within 90 days after the Issuer receives notice or becomes aware of such condition, as the case may be, paragraphs (a) and (b) of this Section shall no longer be applicable and the Issuer shall execute and the Indenture Trustee shall authenticate and deliver certificates representing the Series 2005-1 Notes as provided below. In addition, the Issuer may determine at any time that the Series 2005-1 Notes shall no longer be represented by global certificates and that the provisions of paragraphs (a) and (b) of this Section shall no longer apply to the Series 2005-1 Notes. In such event, the Issuer shall execute and the Indenture Trustee shall authenticate and deliver certificates representing the Series 2005-1 Notes as provided below. Certificates for the Series 2005-1 Notes issued in exchange for a global certificate pursuant to this subsection shall be registered in such names and authorized denominations as the Securities Depository, pursuant to instructions from the Agent Members or otherwise, shall instruct in writing to the Issuer and the Indenture Trustee, and upon which written instructions the Indenture Trustee may rely without investigation. The Indenture Trustee shall promptly deliver such certificates representing the Series 2005-1 Notes to the Persons in whose names such Notes are so registered.

        Section 2.02. Principal Reduction Payments and Redemptions of the Series 2005-1 Notes.     

•         (a)    Mandatory Redemption of Auction Rate Securities .

  • •         (i)    Subject to the provisions of Section 2.02(b) and (d)(ii) hereof and to the provisions of any future Supplemental Indenture, each class of the Auction Rate Securities is subject to mandatory redemption, in whole or in part, at a redemption price equal to the principal balance being redeemed plus accrued interest to the date fixed for redemption, on the first Payment Date occurring each month for such class of the Auction Rate Securities, from amounts remaining on deposit in the Redemption Account and not required to be used to make Principal Reduction Payments or to redeem other Notes pursuant to any Supplemental Indenture. The Class A-1AR Notes through Class A-5AR Notes shall be redeemed prior the redemption of Class A-6AR Notes, and the Class B-1AR Notes and the Class B-2AR Notes shall be redeemed prior the redemption of Class B Notes.

              (ii)    Notice of Redemption . The Indenture Trustee shall cause notice of any redemption pursuant to Section 2.02(a)(i) hereof to be given by mailing a copy of the notice by first-class mail to the Administrator, the Auction Agent and the Noteholder of any Auction Rate Securities designated for redemption in whole or in part, at their address as the same shall last appear upon the registration books, in each case not less than 15 days prior to the redemption date; provided, however, that failure to give such notice, or any defect therein, shall not affect the validity of any proceedings for the redemption of such Auction Rate Securities for which no such failure or defect occurs.

            (b)    Principal Reduction Payments on LIBOR Rate Notes .

    •         (i)    Each class of the LIBOR Rate Notes shall receive reductions of principal pursuant to Principal Reduction Payments to be made on Quarterly Distribution Dates from amounts on deposit in the Redemption Account of the Acquisition Fund for such purpose in an amount

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• • • up to, but not greater than, the amount needed to reduce the outstanding balance of such class of the LIBOR Rate to its Targeted Balance set forth in Appendix B hereto for such Quarterly Distribution Date. If any Principal Reduction Payments on the Class A-1L Notes, the Class A-2L Notes or the Class A-3L Notes are to be made on the same Quarterly Distribution Dates, the Principal Reduction Payments will be made, first , on the Class A-1L Notes until the Class A-1L Notes have been reduced to their Targeted Balance set forth in Appendix B to the Series 2003-2 Supplemental Indenture for such Quarterly Distribution Date, second , on the Class A-2L Notes until the Class A-2L Notes have been reduced to their Targeted Balance set forth in Appendix B hereto for such Quarterly Distribution Date and, third , on the Class A-3L Notes until the Class A-3L Notes have been reduced to their Targeted Balance set forth in Appendix B hereto for such Quarterly Distribution Date. Preferably five, but not less than two Business Days prior to each Quarterly Distribution Date, the Indenture Trustee shall send the Securities Depository written notice with respect to the dollar amount per $1,000 original principal amount thereof, that the Indenture Trustee will be paying to the Securities Depository on the Quarterly Distribution Date for each class of the LIBOR Rate Notes. The Indenture Trustee may, to the extent necessary to avoid payments of fractional cents, reduce scheduled payments by up to $1,000 for each class of the LIBOR Rate Notes. To the extent the Indenture Trustee effects any such reduction, such amount shall be carried over to the next scheduled Principal Reduction Payment Date for that class of the LIBOR Rate Notes. Such notices, which shall clearly indicate that they relate to a reduction of principal, shall contain the Ending Balance Factor and the Indenture Trustee contact's name and telephone number, shall be sent by facsimile (or such other method designated by the Securities Depository) to the Securities Depository's Dividend Department. Failure to make a Principal Reduction Payment on a class of the LIBOR Rate Notes in the amount set forth in the Targeted Amortization Schedule on the Principal Reduction Payment Date shall not constitute an Event of Default under the Indenture.

              (ii)   Notwithstanding subsection (b)(i) of this Section or as provided in a subsequent Supplemental Indenture, if no Senior Notes (other than Senior Notes subject to Principal Reduction Payments) remain outstanding, the LIBOR Rate Notes and any other Senior Notes subject to Principal Reduction Payments are subject to additional reductions of principal pursuant to Principal Reduction Payments to be made on Quarterly Distribution Dates from any amounts remaining on deposit in the Redemption Account of the Acquisition Fund after making the Principal Reduction Payments required pursuant to subsection (b)(i) of this Section. Any such amounts remaining on deposit in the Redemption Account of the Acquisition Fund shall be used to further reduce the outstanding principal amount of any Senior Notes, which may include the LIBOR Rate Notes, subject to Principal Reduction Payments on the next succeeding Quarterly Distribution Date to their Targeted Balances for such succeeding Quarterly Distribution Date. If the outstanding principal amount of all Senior Notes subject to Principal Reduction Payments on such succeeding Quarterly Distribution Date have been reduced to their Targeted Balances for that succeeding Quarterly Distribution Date, then any such amounts remaining on deposit in the Redemption Account of the Acquisition Fund shall be used to further reduce the outstanding principal amount of any Senior Notes, which may include the LIBOR Rate Notes, subject to Principal Reduction Payments on the next succeeding Quarterly Distribution Date until they have been reduced to their Targeted Balances for such next succeeding Quarterly Distribution Date, and the Trustee shall continue this process until the outstanding principal amount of all Senior Notes subject to Principal Reduction Payments have been reduced to zero. If any Principal Reduction Payments on the Class A-1L Notes, the Class A-2L Notes or the Class A-3L Notes are to be made on the same Quarterly Distribution Dates, the Principal Reduction Payments will be made, first , on the Class A-1L Notes until the Class A-1L Notes have been reduced to their

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• • • Targeted Balance set forth in Appendix B to the Series 2003-2 Supplemental Indenture for such Quarterly Distribution Date, second , on the Class A-2L Notes until the Class A-2L Notes have been reduced to their Targeted Balance set forth in Appendix B hereto for such Quarterly Distribution Date and, third , on the Class A-3L Notes until the Class A-3L Notes have been reduced to their Targeted Balance set forth in Appendix B hereto for such Quarterly Distribution Date.

              (iii)  Principal Reduction Payments on the LIBOR Rate Notes will be made on a pro rata basis within each class of the LIBOR Rate Notes receiving Principal Reduction Payments and subsequent to each Principal Reduction Payment, each LIBOR Rate Note will be outstanding in a fractional amount of its original principal amount.

              (iv)   Notice of Principal Reduction . Preferably five, but not less than two Business Days prior to each Principal Reduction Payment Date, the Indenture Trustee shall cause notice of any reduction pursuant to (i) or (ii) of this subsection (b) to be given by mailing a copy of the notice by first class mail to the Administrator and Noteholder of any LIBOR Rate Notes designated for reduction in whole or in part, at their address as the same shall last appear upon the registration books on the reduction date; provided, however, that failure to give such notice, or any defect therein, shall not affect the validity of any proceedings for the reduction of such LIBOR Rate Notes.

            (c)    Optional Redemption or Purchase .

    •         (i)     Optional Redemption or Purchase of Series 2005-1 Notes . Subject to the provisions of Section 2.02(d) hereof, the Series 2005-1 Notes are subject to redemption or purchase at the option of the Issuer exercised by an Issuer Order, in whole only, on any Payment Date on which the aggregate current principal balance of all the Notes issued under the Indenture is less than or equal to 10% of the initial aggregate principal balance of all the Notes issued under the Indenture on their respective Closing Date, at a redemption price equal to (A) the principal balance plus accrued interest to the date fixed for redemption and (B) any Carry-over Amount and any interest accrued on any Carry-over Amount to the date fixed for redemption, from the proceeds of funds received by the Indenture Trustee and deposited in the Revenue Fund, the Acquisition Fund and the Reserve Fund. On the Payment Date fixed for redemption or purchase in such Issuer Order (which Issuer Order shall be received by the Indenture Trustee not less then 16 days prior to such redemption), the Issuer shall deposit or cause to be deposited in or transferred to the Redemption Account of the Acquisition Fund (from the Revenue Fund) an amount sufficient to redeem all of the Notes, less amounts on deposit in the Reserve Fund. On such redemption date the Indenture Trustee shall transfer amounts in the Reserve Fund to the Redemption Account of the Acquisition Fund and effect the redemption of all the Notes.

              (ii)    Notice of Redemption and Purchase . The Indenture Trustee shall cause notice of any redemption or purchase pursuant to Section 2.02(c)(i) hereof to be given by mailing a copy of the notice by first-class mail to the Administrator, the Auction Agent, if applicable, and the Noteholder of any Series 2005-1 Notes designated for redemption or purchase in whole or in part, at their address as the same shall last appear upon the registration books, in each case not less than 15 days prior to the redemption or purchase date; provided, however, that failure to give such notice, or any defect therein, shall not affect the validity of any proceedings for the redemption or purchase of such Series 2005-1 Notes for which no such failure or defect occurs.

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• •         (d)    Partial Redemption .

    •         (i)    If less than all of the Auction Rate Securities are to be redeemed or purchased pursuant to Section 2.02(a)(i) hereof, the Auction Rate Securities to be redeemed or purchased shall be redeemed or purchased on a monthly basis in ascending order of Stated Maturity and, within same Stated Maturities, from the Auction Rate Securities with the earliest Payment Date during the month, subject to Section 2.02(d)(ii) hereof. If two or more classes of Auction Rate Securities have the same Stated Maturity and the same Payment Date, such Auction Rate Securities shall be redeemed on a pro rata basis among or between such classes, subject to Section 2.02(d)(ii) hereof.

              (ii)   All of the Class A Notes shall be redeemed prior to redemption of any Class B Notes; provided, however, upon the Indenture Trustee's receipt of an Issuer Order certifying that the ratio of the Value of the Trust Estate to the Value of the Senior Notes and the Subordinate Notes then Outstanding exceeds 101.5% and the ratio of the Value of the Trust Estate to the Value of the Senior Notes then Outstanding exceeds 104%, or such other percentages that satisfy the Rating Agency Condition, the Indenture Trustee shall redeem Class B Notes while Class A Notes remain Outstanding until the Value of the Trust Estate to the Value of the Notes equals the percentages described in this sentence after giving effect to the redemption of Class B Notes. The Indenture Trustee may conclusively rely upon such certification without duty to know, determine or further examine such Issuer Order.

              (iii)  If less than all of a class of the Auction Rate Securities are to be redeemed, the Auction Rate Securities to be redeemed shall be selected by lot in such manner as the Indenture Trustee shall determine. In the event of a redemption pursuant to Section 2.02(a)(i) hereof whereby funds remain in an amount below the Authorized Denomination, such remaining funds shall be transferred to the Revenue Fund.

              (iv)  In case an Auction Rate Security is of a denomination larger than an Authorized Denomination, a portion of such Auction Rate Security (in an Authorized Denomination) may be redeemed. Upon surrender of any Auction Rate Security for redemption in part only, the Issuer shall execute and the Indenture Trustee shall authenticate and deliver to the Noteholder thereof, the cost of which shall be paid by the Issuer, a new Auction Rate Security or Auction Rate Securities of the same series, maturity and of authorized denominations, in an aggregate principal amount equal to the unredeemed portion of the Auction Rate Security surrendered.

        Section 2.03. Delivery of Series 2005-1 Notes.     Upon the execution and delivery of this Supplemental Indenture, the Issuer shall execute and deliver to the Indenture Trustee and the Indenture Trustee shall authenticate the Series 2005-1 Notes and deliver the Class A Notes and the Class B Notes to The Depository Trust Company; provided, however, prior to the delivery by the Indenture Trustee of any of the Series 2005-1 Notes, there shall have been filed with or delivered to the Indenture Trustee the following:

•         (a)   an Issuer Order authorizing the execution and delivery of this Supplemental Indenture and the issuance of the Series 2005-1 Notes;

          (b)   duly executed copies of this Supplemental Indenture and a copy of the Indenture; and

          (c)   rating letters from each Rating Agency stating (i) that the Class A Notes have been rated "AAA" by Fitch and S&P and "Aaa" by Moody's; (ii) that the Class B Notes have been rated "A" by Fitch and S&P and "A2" by Moody's and (iii) that the issuance of the Series 2005-1 Notes will not adversely affect the ratings assigned to the Series 2003-1 Notes or the Series 2003-2 Notes or that the ratings on the Series 2003-1 Notes or the Series 2003-2 Notes have been confirmed.

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        Section 2.04. Trustee's Authentication Certificate.     The Indenture Trustee's authentication certificate upon the Series 2005-1 Notes shall be substantially in the forms provided in Exhibits A-1, A-2 and A-3 hereto. No Series 2005-1 Note shall be secured hereby or entitled to the benefit hereof, or shall be valid or obligatory for any purpose, unless a certificate of authentication, substantially in such form, has been duly executed by the Indenture Trustee; and such certificate of the Indenture Trustee upon any Series 2005-1 Note shall be conclusive evidence and the only competent evidence that such Note has been authenticated and delivered hereunder. The Indenture Trustee's certificate of authentication shall be deemed to have been duly executed by it if manually signed by an authorized officer of the Indenture Trustee, but it shall not be necessary that the same person sign the certificate of authentication on all of the Series 2005-1 Notes issued hereunder.

        Section 2.05. Deposit of Series 2005-1 Note Proceeds.     Upon the issuance and delivery of the Series 2005-1 Notes, the Indenture Trustee shall deposit the net proceeds thereof (i.e., net of Underwriters' discount of $1,750,000.00):

•         (a)   an amount equal to $489,500,000.00 shall be deposited to the 2005-1 Acquisition Account;

          (b)   an amount equal to $3,750,000.00 shall be deposited to the Capitalized Interest Account; and

          (c)   an amount equal to $5,000,000.00 shall be deposited to the Reserve Fund.

        Section 2.06. Forms of Series 2005-1 Notes.     The LIBOR Rate Notes shall be in substantially the form set forth in Exhibit A-1 hereto, the Class A-6AR Notes shall be in substantially the form set forth in Exhibit A-2 hereto and the Class B Notes shall be in substantially the form set forth in Exhibit A-3 hereto, each with such variations, omissions and insertions as may be necessary.

        Section 2.07. Conditions Precedent.     Each of the Series 2005-1 Notes shall be executed, authenticated and delivered on the Closing Date for such Series 2005-1 Notes set forth herein subject to the satisfaction of the conditions precedent set forth in Section 2.09 of the Original Indenture and Section 2.03 hereof.

        Section 2.08. Issuer Covenants with Respect to Principal Reduction Payments.     No Additional Notes may be issued by the Issuer which have Principal Reduction Payments or, except as provided in this Section, Stated Maturities (or mandatory sinking fund payments) prior to May 25, 2014 which are payable prior to the Principal Reduction Payments on the LIBOR Rate Notes; provided, however, the Issuer may issue Additional Notes with Principal Reduction Payments which are payable concurrently with the Principal Reduction Payments on the LIBOR Rate Notes or Additional Notes with Stated Maturities (or mandatory sinking fund payments) prior to May 25, 2014, if the Issuer reasonably determines, on the date of issuance of such Additional Notes, that the issuance of such Additional Notes will not adversely affect the sufficiency of the amounts directed to make Principal Reduction Payments on the LIBOR Rate Notes in accordance with the Targeted Balances set forth on Appendix B hereto.

ARTICLE III
FUNDS AND ACCOUNTS

        Section 3.01. Acquisition Fund.     The Indenture Trustee is hereby directed to establish an Account within the Acquisition Fund to be known as the "2005-1 Acquisition Account." The Indenture Trustee shall deposit the proceeds described in Section 2.05(a) hereof to the 2005-1 Acquisition Account on the Closing Date. Moneys in the 2005-1 Acquisition Account shall be used as described in Section 5.02 of the Indenture. On August 31, 2005, or such later date consented to by the Rating Agencies rating the Notes, any proceeds of the Series 2005-1 Notes remaining in the 2005-1 Acquisition Account shall be transferred to the Redemption Account and the 2005-1 Acquisition Account shall be closed.

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        The Indenture Trustee is hereby directed to continue the Redemption Account of the Acquisition Fund established pursuant to Section 3.01 of the Series 2003-1 Supplemental Indenture. All Recoveries of Principal deposited to the Acquisition Fund shall be transferred to the Redemption Account. In addition, any amounts permitted to be transferred to the Redemption Account from the Revenue Fund pursuant to Section 5.03(c) of the Indenture shall be deposited to the Redemption Account. Moneys in the Redemption Account shall be used (i)  first , to make the next scheduled Principal Reduction Payments on Notes pursuant to the provisions of the Supplemental Indentures authorizing such Notes (or to retain therein an amount sufficient to make such next Principal Reduction Payments), second , to mandatorily redeem Notes pursuant to the provisions of the Supplemental Indentures authorizing such Notes and, third , to make additional Principal Reduction Payments on Notes pursuant to the provisions of the Supplemental Indentures authorizing such Notes or (ii) as otherwise directed in a Supplemental Indenture.

        Section 3.02. Capitalized Interest Account.     The Indenture Trustee is hereby directed to continue the Capitalized Interest Account of the Acquisition Fund established pursuant to Section 3.02 of the Series 2003-1 Supplemental Indenture. Moneys on deposit in the Capitalized Interest Account shall be transferred to the Revenue Fund by the Indenture Trustee as needed to make the transfers described in Sections 5.03(b)(i), (iii) and (v) of the Indenture. Notwithstanding the provisions of Section 3.02 of the Series 2003-1 Supplemental Indenture or Section 3.02 of the Series 2003-2 Supplemental Indenture, on January 1, 2007, all amounts in excess of $3,750,000 in the Capitalized Interest Account shall be transferred to the Redemption Account, and on June 1, 2008, any moneys remaining in the Capitalized Interest Account shall be transferred to the Redemption Account, and the Capitalized Interest Account shall be closed.

ARTICLE IV
GENERAL PROVISIONS

        Section 4.01. Date of Execution.     This Supplemental Indenture for convenience and for the purpose of reference is dated as of March 1, 2005.

        Section 4.02. Laws Governing.     It is the intent of the parties hereto that this Supplemental Indenture shall in all respects be governed by the laws of the State of Colorado.

        Section 4.03. Severability.     If any covenant, agreement, waiver or part thereof in this Supplemental Indenture contained be forbidden by any pertinent law or under any pertinent law be effective to render this Supplemental Indenture invalid or unenforceable or to impair the lien hereof, then each such covenant, agreement, waiver, or part thereof shall itself be and is hereby declared to be wholly ineffective, and this Supplemental Indenture shall be construed as if the same were not included herein.

        Section 4.04. Exhibits and Appendices.     The terms of each Exhibit and Appendix attached to this Supplemental Indenture are incorporated herein in all particulars.

        Section 4.05. Limitation of Liability of the Delaware Trustee.     It is expressly understood and agreed by the parties hereto that (a) this Supplemental Indenture is executed and delivered by the Delaware Trustee, not individually or personally but solely as Delaware Trustee of the Issuer, in the exercise of the powers and authority conferred and vested in it under the Trust Agreement; (b) each of the representations, undertakings and agreements herein made on the part of the Issuer is made and intended not as personal representations, undertakings and agreements by the Delaware Trustee but is made and intended for the purpose of binding only the Issuer; and (c) under no circumstances shall the Delaware Trustee be personally liable for the payment of any indebtedness or expenses of the Issuer or be liable for the breach or failure of any obligation, representation, warranty or covenant made or undertaken by the Issuer under this Supplemental Indenture.

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ARTICLE V
APPLICABILITY OF INDENTURE

        The provisions of the Indenture are hereby ratified, approved and confirmed, except as otherwise expressly modified by this Supplemental Indenture. The representations, warranties and covenants contained in the Indenture (except as expressly modified herein) are hereby reaffirmed with the same force and effect as if fully set forth herein and made again as of the date hereof.

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        IN WITNESS WHEREOF, the Issuer and the Indenture Trustee have caused this Supplemental Indenture to be executed by their respective Authorized Officers, to evidence its acceptance of the trusts hereby created, has caused this Supplemental Indenture to be executed in its name and behalf, all in multiple counterparts, each of which shall be deemed an original, and the Issuer and the Indenture Trustee have caused this Supplemental Indenture to be dated as of the date herein above first shown, although actually executed on the dates shown in the acknowledgments hereafter appearing.

[Signature Page to Series 2005-1 Supplemental Indenture of Trust]

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APPENDIX A

CERTAIN TERMS AND PROVISIONS OF
THE AUCTION RATE SECURITIES

ARTICLE I
DEFINITIONS

        Except as provided below in this Section, all terms which are defined in the Indenture and Article I of this Supplemental Indenture shall have the same meanings, respectively, in this Appendix A as such terms are given in the Indenture and Article I of this Supplemental Indenture. In addition, the following terms shall have the following respective meanings:

        " All Hold Rate " means the Applicable LIBOR Rate less .20%; provided, that in no event shall the applicable All Hold Rate be greater than the applicable Maximum Rate.

        " Applicable LIBOR Rate " means, (a) for Auction Periods of 35 days or less, One-Month LIBOR, (b) for Auction Periods of more than 35 days but less than 91 days, Three-Month LIBOR, (c) for Auction Periods of more than 90 days but less than 181 days, Six-Month LIBOR, and (d) for Auction Periods of more than 180 days, One-Year LIBOR.

        " Auction " means the implementation of the Auction Procedures on an Auction Date.

        " Auction Agent " means the Initial Auction Agent under the Initial Auction Agent Agreement unless and until a Substitute Auction Agent Agreement becomes effective, after which "Auction Agent" means the Substitute Auction Agent.

        " Auction Agent Agreement " means the Initial Auction Agent Agreement unless and until a Substitute Auction Agent Agreement is entered into, after which "Auction Agent Agreement" means such Substitute Auction Agent Agreement.

        " Auction Agent Fee " has the meaning set forth in the Auction Agent Agreement.

        " Auction Date " means, initially, April 13, 2005 with respect to the Class A-6AR Notes, and April 13, 2005 with respect to the Class B Notes, and thereafter, the Business Day immediately preceding the first day of each Auction Period for each respective class, other than:

•         (a)   each Auction Period commencing after the ownership of the applicable Auction Rate Securities is no longer maintained in Book-entry Form by the Securities Depository;

          (b)   each Auction Period commencing after and during the continuance of a Payment Default; or

          (c)   each Auction Period commencing less than two Business Days after the cure or waiver of a Payment Default.

        Notwithstanding the foregoing, the Auction Date for one or more Auction Periods may be changed pursuant to Section 2.02(h) of this Appendix A.

        " Auction Note Interest Rate " means the variable rate of interest per annum borne by Auction Rate Securities for each Auction Period and determined in accordance with the provisions of Sections 2.01 and 2.02 of this Appendix A; provided, however, that in the event of a Payment Default, the Auction Note Interest Rate shall equal the applicable Non-Payment Rate; provided, further, however that such Auction Note Interest Rate shall in no event exceed the lesser of the Net Loan Rate and the Maximum Rate.

        " Auction Period " means the Interest Period applicable to the Auction Rate Securities during which time the Interest Rate is determined pursuant to Section 2.02(a) of this Appendix A, which Auction Period (after the Initial Period for such class) initially shall consist generally of 28 days for the Auction Rate Securities, as the same may be adjusted pursuant to Sections 2.01 and 2.02(g) of this Appendix A.

        " Auction Period Adjustment " means an adjustment to the Auction Period as provided in Section 2.02(g) of this Appendix A.

        " Auction Procedures " means the procedures set forth in Section 2.02(a) of this Appendix A by which the Auction Rate is determined.

        " Auction Rate " means the rate of interest per annum that results from implementation of the Auction Procedures and is determined as described in Section 2.02(a)(iii)(B) of this Appendix A.

        " Auction Rate Securities " means, collectively, the Class A-6AR Notes and the Class B Notes.

        " Authorized Denominations " means $50,000 and any integral multiple thereof.

        " Available Auction Rate Securities " has the meaning set forth in Section 2.02(a)(iii)(A)(1) of this Appendix A.

        " Bid " has the meaning set forth in Section 2.02(a)(i)(A) of this Appendix A.

        " Bid Auction Rate " has the meaning set forth in Section 2.02(a)(iii)(A) of this Appendix A.

        " Bidder " has the meaning set forth in Section 2.02(a)(i)(A) of this Appendix A.

        " Bond Equivalent Yield " means with respect to any security with a maturity of six months or less the rate for which is quoted in The Wall Street Journal on a bank discount basis, a yield (expressed as a percentage) calculated in accordance with the following formula and rounded up to the nearest one-hundredth of one percent:

where "Q" refers to the per annum interest rate for the security quoted on a bank discount basis and expressed as a decimal, "N" refers to 365 or 366 (days), as the case may be, and "T" refers to the number of days to maturity.

        " Book-Entry Form " or " Book-Entry System " means a form or system under which (a) the beneficial right to principal and interest may be transferred only through a book entry; (b) physical securities in registered form are issued only to a Securities Depository or its nominee as Noteholder, with the securities "immobilized" to the custody of the Securities Depository; and (c) the book entry is the record that identifies the owners of beneficial interests in that principal and interest.

        " Broker-Dealer " means, Citigroup Global Markets, Inc. or any other broker or dealer (each as defined in the Securities Exchange Act of 1934, as amended), commercial bank or other entity permitted by law to perform the functions required of a Broker-Dealer set forth in the Auction Procedures that (a) is a Participant (or an affiliate of a Participant); (b) has been appointed as such by the Issuer pursuant to Section 2.02(f) of this Appendix A; and (c) has entered into a Broker-Dealer Agreement that is in effect on the date of reference.

        " Broker-Dealer Agreements " means the agreements between the Auction Agent and the Broker-Dealers, and approved by the Issuer, pursuant to which the Broker-Dealers agree to participate in Auctions as set forth in the Auction Procedures, as from time to time amended or supplemented. The Broker-Dealer Agreements shall be in substantially the form of the Broker-Dealer Agreements, each dated as of March 1, 2005, among the Issuer, Deutsche Bank Trust Company Americas, as Auction Agent, and Citigroup Global Markets, Inc.

        " Broker-Dealer Fee " has the meaning set forth in the Auction Agent Agreement.

A-2

        " Business Day " means any day other than a Saturday, Sunday, holiday or other day on which the New York Stock Exchange or banks located in New York, New York, or in the city in which the principal office of the Indenture Trustee or the Auction Agent is located, are authorized or permitted by law or executive order to close; provided that with respect to Auction Dates such term shall exclude April 14 and 15 and December 30 and 31 and such other dates as may be agreed to in writing by the Auction Agent, the Broker-Dealers and the Issuer.

        " Cap Rate " means, with respect to any Interest Period applicable to the Auction Rate Securities, the lesser of (a) the applicable Maximum Rate, and (b) the Net Loan Rate in effect for such Interest Period.

        " Carry-over Amount " means, for any Interest Period during which interest is calculated at the Net Loan Rate, the excess, if any, of (a) the amount of interest on an Auction Rate Security that would have accrued with respect to the related Interest Period at the lesser of (i) the applicable Auction Rate; and (ii) the Maximum Rate; over (b) the amount of interest on such Auction Rate Security actually accrued with respect to such Auction Rate Security with respect to such Interest Period based on the Net Loan Rate, together with the unreduced portion of any such excess from prior Interest Periods; provided that any reference to "principal" or "interest" in the Supplemental Indenture and in this Appendix A and the Auction Rate Securities shall not include within the meanings of such words any Carry-over Amount or any interest accrued on any Carry-over Amount.

        " Commercial Paper Rate (90-day) " means the rate determined at the end of each calendar quarter using the daily average of that quarter's bond equivalent 3-Month Financial Commercial Paper rates. The daily bond equivalent rates are calculated from the Three-Month Financial Commercial Paper discount rates published in the Federal Reserve's H.15 report. On weekends, holidays and any other day when no H.15 rates are available, the rate from the most recent published date is used.

        " Effective Interest Rate " means, with respect to any Financed Student Loan, the interest rate per annum payable by the borrower as of the last day of the calendar quarter borne by such Financed Student Loan after giving effect to any reduction in such interest rate pursuant to borrower incentives, (a) less all accrued rebate fees on such Financed Student Loan constituting Consolidation Loans paid during such calendar quarter expressed as a percentage per annum; and (b) plus all accrued Interest Benefit Payments and Special Allowance Payments applicable to such Financed Student Loan during such calendar quarter expressed as a percentage per annum.

        " Eligible Carry-Over Make-Up Amount " means, with respect to each Interest Period relating to the Auction Rate Securities as to which, as of the first day of such Interest Period, there is any unpaid Carry-over Amount, an amount equal to the lesser of (a) interest computed on the principal balance of the Auction Rate Securities in respect to such Interest Period at a per annum rate equal to the excess, if any, of the Net Loan Rate over the Auction Rate, together with the unreduced portion of any such excess from prior Interest Periods; and (b) the aggregate Carry-over Amount remaining unpaid as of the first day of such Interest Period together with interest accrued and unpaid thereon through the end of such Interest Period.

        " Existing Owner " means (a) with respect to and for the purpose of dealing with the Auction Agent in connection with an Auction, a Person who is a Broker-Dealer listed in the Existing Owner Registry at the close of business on the Business Day immediately preceding the Auction Date for such Auction; and (b) with respect to and for the purpose of dealing with the Broker-Dealers in connection with an Auction, a Person who is a beneficial owner of Auction Rate Securities.

        " Existing Owner Registry " means the registry of Persons who are owners of the Auction Rate Securities, maintained by the Auction Agent as provided in the Auction Agent Agreement.

        " Hold Order " has the meaning set forth in Section 2.02(a)(i)(A) of this Appendix A.

A-3

        " Initial Auction Agent " means Deutsche Bank Trust Company Americas, its successors and assigns.

        " Initial Auction Agent Agreement " means the Auction Agent Agreement dated as of March 1, 2005, by and among the Issuer, the Indenture Trustee and the Initial Auction Agent, including any amendment thereof or supplement thereto.

        " Initial Period " means, as to Auction Rate Securities, the period commencing on the Closing Date and continuing through the day immediately preceding the Initial Rate Adjustment Date for such Auction Rate Securities.

        " Initial Rate " means, with respect to the Class A-6AR, 2.95% and, with respect to the Class B Notes, 3.05%.

        " Initial Rate Adjustment Date " means, with respect to the Class A-6AR Notes, April 14, 2005 and, with respect to the Class B Notes, April 14, 2005.

        " Interest Period " means, with respect to a class of the Auction Rate Securities, the Initial Period and each period commencing on an Interest Rate Adjustment Date for such class and ending on the day before (a) the next Interest Rate Adjustment Date for such class; or (b) the Stated Maturity of such class, as applicable.

        " Interest Rate Adjustment Date " means the Business Day immediately following the Auction Date, such day being the date on which an Auction Note Interest Rate is effective, and shall mean, with respect to the Auction Rate Securities, the date of commencement of each Auction Period.

        " Interest Rate Determination Date " means, with respect to a class of the Auction Rate Securities, the Auction Date, or if no Auction Date is applicable to such class, the Business Day immediately preceding the date of commencement of an Auction Period.

        " Maximum Rate " means the least of (a) either (i) the Applicable LIBOR Rate plus 1.50% (if the ratings assigned by Moody's, S&P and Fitch to the Auction Rate Securities are "Aaa," "AAA" and "AAA," respectively, or better); (ii) the Applicable LIBOR Rate plus 2.50% (if any one of the ratings assigned by Moody's, S&P and Fitch to the Auction Rate Securities is less than "Aaa," "AAA" and "AAA," respectively, and greater than or equal to "A3," "A-" and "A-," respectively); or (iii) the Applicable LIBOR Rate plus 3.50% (if any one of the ratings assigned by Moody's, S&P and Fitch to the Auction Rate Securities is less than "A3," "A-" and "A-" respectively); (b) 16%; and (c) the highest rate the Issuer may legally pay, from time to time, as interest on the Auction Rate Securities. For purposes of the Auction Agent and the Auction Procedures, the ratings referred to in this definition shall be the last ratings of which the Auction Agent has been given written notice pursuant to the Auction Agent Agreement.

        " Net Loan Rate " means, respect to any Interest Period applicable to the Auction Rate Securities, the rate of interest per annum (rounded to the next highest one-hundredth of one percent) equal to (a) the weighted average Effective Interest Rate of the Financed Student Loans for the calendar quarter immediately preceding such Interest Period, as determined by the Issuer on the last day of such calendar quarter, less (b) the sum of (i) Realized Losses with respect to the Financed Eligible Loans for the most recently completed calendar quarter and (ii) the Program Expense Percentage on the Financial Student Loans, as determined by the Issuer on the last day of each calendar year. In making the determinations in (a) and (b) of this definition of "Net Loan Rate," the Issuer shall take into account as an increase to such Net Loan Rate the receipt of any Reciprocal Payment and as a decrease to any Issuer Derivative Payment. The determinations made by the Issuer in (a) and (b) of this definition of "Net Loan Rate" shall be given in writing to the Auction Agent, the Indenture Trustee and each Broker-Dealer immediately upon their respective calculation dates. The Issuer shall have no obligation to compute any component of the Net Loan Rate except on an applicable Auction Date on which the Auction Rate is equal to the Maximum Rate.

A-4

        " Non-Payment Rate " means One-Month LIBOR plus 1.50%.

        " One-Month LIBOR ," " Three-Month LIBOR ," " Six-Month LIBOR " or " One-Year LIBOR ," means the offered rate, as determined by the Auction Agent or Indenture Trustee, as applicable, of the Applicable LIBOR Based Rate for United States dollar deposits which appears on Telerate Page 3750, as reported by Bloomberg Financial Markets Commodities News (or such other page as may replace Telerate Page 3750 for the purpose of displaying comparable rates) as of approximately 11:00 a.m., London time, on the Interest Rate Determination Date; provided, that if on any calculation date, no rate appears on Telerate Page 3750 as specified above, the Auction Agent or Indenture Trustee, as applicable, shall determine the arithmetic mean of the offered quotations of four major banks in the London interbank market, for deposits in United States dollars for the respective periods specified above to the banks in the London interbank market as of approximately 11:00 a.m., London time, on such calculation date and in a principal amount of not less than $1,000,000 that is representative of a single transaction in such market and at such time, unless fewer than two such quotations are provided, in which case, the Applicable LIBOR Based Rate shall be the arithmetic mean of the offered quotations that leading banks in New York City selected by the Auction Agent or Indenture Trustee, as applicable, are quoting on the relevant Interest Rate Determination Date for loans in United States dollars to leading European banks in a principal amount of not less than $1,000,000 that is representative of a single transaction in such market at such time. All percentages resulting from such calculations shall be rounded upwards, if necessary, to the nearest one-hundredth of one percent.

        " Order " has the meaning set forth in Section 2.02(a)(i)(A) of this Appendix A.

        " Payment Date " means (a) so long as Auction Rate Securities bear interest at an Auction Note Interest Rate for an Interest Period of not greater than 90 days, the Business Day immediately following the expiration of the Initial Period for such Auction Rate Securities, and each related Auction Period thereafter; and (b) if and for so long as Auction Rate Securities bear interest at an Auction Note Interest Rate for an Interest Period of greater than 90 days, the first Business Day occurring in each February, May, August and November for such Auction Rate Securities.

        " Payment Default " means, with respect to the Auction Rate Securities, (a) a default in the due and punctual payment of any installment of interest on such Auction Rate Securities, or (b) a default in the due and punctual payment of any interest on and principal of such Auction Rate Securities at their maturity.

        " Potential Owner " means any Person (including an Existing Owner that is (a) a Broker-Dealer when dealing with the Auction Agent and (b) a potential beneficial owner when dealing with a Broker-Dealer) who may be interested in acquiring Auction Rate Securities (or, in the case of an Existing Owner thereof, an additional principal amount of Auction Rate Securities).

        " Program Expense Percentage " means, the percentage that all Program Expenses (other than Consolidation Loan rebate fees) estimated for the next 12 months represent of the principal amount of the Notes, which as of March 15, 2005 is 0.50%, and which the Issuer shall calculate annually on the last day of each calendar year and provide to the Indenture Trustee, the Auction Agent and the Broker-Dealers in the form of an Issuer Order. Any adjustment in the Program Expense Percentage shall be certified to the Indenture Trustee in an Issuer Order and shall be effective beginning on the first Interest Rate Determination Date following each such calculation.

        " PSA " means the Public Securities Association, its successors and assigns.

        " Regular Record Date " means the Business Day next preceding the applicable Payment Date.

        " S&P " means Standard & Poor's Ratings Services, a Division of The McGraw-Hill Companies, Inc., its successors and assigns.

        " Sell Order " has the meaning set forth in Section 2.02(a)(i)(A) of this Appendix A.

A-5

        " Submission Deadline " means 1:00 p.m., New York City time, on any Auction Date or such other time on any Auction Date by which the Broker-Dealers are required to submit Orders to the Auction Agent as specified by the Auction Agent from time to time.

        " Submitted Bid " has the meaning set forth in Section 2.02(a)(iii)(A) of this Appendix A.

        " Submitted Hold Order " has the meaning set forth in Section 2.02(a)(iii)(A) of this Appendix A.

        " Submitted Order " has the meaning set forth in Section 2.02(a)(iii)(A) of this Appendix A.

        " Submitted Sell Order " has the meaning set forth in Section 2.02(a)(iii)(A) of this Appendix A.

        " Substitute Auction Agent " means the Person with whom the Issuer and the Indenture Trustee enter into a Substitute Auction Agent Agreement.

        " Substitute Auction Agent Agreement " means an auction agent agreement containing terms substantially similar to the terms of the Initial Auction Agent Agreement, whereby a Person having the qualifications required by Section 2.02(e) of this Appendix A agrees with the Indenture Trustee and the Issuer to perform the duties of the Auction Agent under this Appendix A.

        " Sufficient Bids " has the meaning set forth in Section 2.02(a)(iii)(A) of this Appendix A.

        " Variable Rate " means the variable rate of interest per annum, including the Initial Rate, borne by each class of Auction Rate Securities during the Initial Period for such class, and each Interest Period thereafter as such rate of interest is determined in accordance with the provisions of Article II of this Appendix A.

ARTICLE II
TERMS AND ISSUANCE

        Section 2.01. Auction Rate and Carry-Over Amounts.     During the Initial Period, each class of Auction Rate Securities shall bear interest at the Initial Rate for such class. Thereafter, and except with respect to an Auction Period Adjustment, the Auction Rate Securities shall bear interest at an Auction Note Interest Rate based on a 28-day Auction Period for the Auction Rate Securities, as determined pursuant to this Section 2.01 and Section 2.02 of this Appendix A.

        For the Auction Rate Securities during the Initial Period and each Auction Period thereafter, interest at the applicable Auction Rate Securities Interest Rate shall accrue daily and shall be computed for the actual number of days elapsed on the basis of a year consisting of 360 days and rounding the resultant figure to the fifth decimal place.

        The Auction Note Interest Rate to be borne by the Auction Rate Securities after such Initial Period for each Auction Period until an Auction Period Adjustment, if any, shall be determined as described below. Unless otherwise specified in an Issuer Order, each such Auction Period after the Initial Period shall commence on and include the day following the expiration of the immediately preceding Auction Period and terminate on and include the (i) Wednesday (unless such day is not followed by a Business Day, in which case on the next succeeding day that is followed by a Business Day) of the following fourth week in the case of the Class A-6AR Notes and (ii) Wednesday (unless such day is not followed by a Business Day, in which case on the next succeeding day that is followed by a Business Day) of the following fourth week in the case of the Class B Notes; provided, however, that in the case of the Auction Period that immediately follows the Initial Period for the Auction Rate Securities, such Auction Period shall commence on the Initial Rate Adjustment Date. By way of example, if an Interest Period ordinarily would end on a Wednesday, but the following Thursday is not a Business Day, the Interest Period will end on that Thursday and the new Interest Period will begin on Friday. The Auction Note Interest Rate of the Auction Rate Securities for each Auction Period shall

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be the Auction Rate in effect for such Auction Period as determined in accordance with Section 2.02(a) of this Appendix A.

        Notwithstanding the foregoing, unless otherwise specified in an Issuer Order, if an Auction is scheduled to occur for the next Auction Period on a date that was reasonably expected to be a Business Day, but such Auction does not occur because such date is later not considered to be a Business Day, the Auction shall nevertheless be deemed to have occurred, and the applicable Auction Note Interest Rate in effect for the next Auction Period will be the Auction Note Interest Rate in effect for the preceding Auction Period and such Auction Period will generally be 28 days in duration, beginning on the calendar day following the date of the deemed Auction and ending on (and including) the applicable (i) Wednesday (unless such day is not followed by a Business Day, in which case on the next succeeding day that is followed by a Business Day) of the following fourth week in the case of the Class A-6AR Notes and (ii)&