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                                                                     Exhibit 4.2

                                                                  EXECUTION COPY
                                                                  --------------

                  FIRST AMENDMENT, dated as of March 6, 2000 (this "Amendment")
to the Amended and Restated Trust Agreement, dated as of September 1, 1999 (the
"Agreement") between KEY BANK USA, NATIONAL ASSOCIATION, as Depositor (the
"Depositor"), and BANK ONE, NATIONAL ASSOCIATION, not in its individual capacity
but solely as Eligible Lender Trustee (the " Trustee"), concerning the creation
of KeyCorp Student Loan Trust 1999-B (the "Trust"), and the issuance by the
Trust of its Floating Rate Asset-Backed Notes, Class A-1, Class A-2, and Class M
(collectively, the "Notes") and Floating Rate Asset-Backed Certificates (the
"Certificates"). Terms not otherwise defined in this Amendment shall have the
meanings ascribed to such terms in the Agreement.

                              W I T N E S S E T H :
                              - - - - - - - - - -

                  WHEREAS, KeyBank National Association ("KBNA") owns 99% of the
Certificates, and Key Bank USA, National Association ("KBUSA") owns 1% of the
Certificates; and

                  WHEREAS, KBNA and KBUSA desire to amend the Certificates to
reduce the Certificate Rate and to create a new uncertificated strip that would
be entitled to receive the excess of interest payable at the original
Certificate Rate over interest payable at the new reduced Certificate Rate, on a
pari passu basis with the Certificates; and

                  WHEREAS, the parties to the Agreement desire to execute this
Amendment to provide for such changes in the quarterly cash flow; and

                  WHEREAS, Key Bank USA, National Association, in its capacity
as Cap Provider, has consented to the execution and delivery of this Amendment;

                  NOW, THEREFORE, in consideration of the premises and mutual
agreements herein contained, it is hereby agreed as follows:

                  ARTICLE 1. AMENDMENTS

                  1.1 AMENDMENTS TO DEFINITIONS.The provisions of Sections 1.1,
1.2 and 1.3 of the First Amendment, dated as of March 6, 2000, to the Sale and
Servicing Agreement, dated as of September 1, 1999, among the Issuer, KBUSA, as
Seller, Master Servicer and Administrator, and Bank One, National Association,
not in its individual capacity but solely as Eligible Lender Trustee, are hereby
incorporated in their entirety into this Amendment and the Agreement is so
modified to reflect such changes.

                  1.2 AMENDMENT TO ARTICLE II.  Section 2.01 of the Agreement
is hereby supplemented by the addition of the following new paragraph at the end
of such Section 2.01:



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                  "The Certificate Strip is an uncertificated, non-voting
interest in the Trust entitled to payments of interest at the Certificate Strip
Rate as set forth herein and in the Sale and Servicing Agreement. KBNA is the
sole holder of the Certificate Strip and such interest is non-transferable by
KBNA to any party, except to an Affiliate thereof in a transaction exempt from
registration under the Securities Act."

                  1.3 AMENDMENTS TO ARTICLE V. Section 5.01(a) of the Agreement
is hereby deleted in its entirety and the following is substituted in lieu
thereof:

                  "(a) On each Distribution Date, the Eligible Lender Trustee
will distribute, on a pari passu basis, to (i) holders of the Certificates, on a
pro rata basis, the Certificateholders' Distribution Amount and any
Certificateholders' Interest Index Carryover, if applicable, and (ii) to the
holder of the Certificate Strip, the Certificate Strip Interest Distribution
Amount and any Certificate Strip Interest Index Carryover, if applicable, each
in the amounts received from the Indenture Trustee pursuant to Sections 5.05 and
5.06 of the Sale and Servicing Agreement on such Distribution Date.

                  (b) Section 5.02 is hereby amended by the addition of the
following sentence at the end of such Section 5.02:

                  "Any distributions required to be made to the holder of the
Certificate Strip on any Distribution Date shall be paid to KBNA (or its
permitted assignee) by wire transfer in immediately available funds to the
account designated by KBNA (or its permitted assignee)."

         ARTICLE 2 MISCELLANEOUS

                  2.1 EFFECTIVE DATE. The effective date of this Amendment shall
be February 25, 2000 (the "Effective Date"). The Agreement shall read to
incorporate the provisions of this Amendment on and after the Effective Date and
the Agreement shall be read without reference to this Amendment for all dates
and periods prior to the Effective Date.

                  2.2 LIMITED EFFECT. Except as expressly amended by this
Amendment, all of the provisions, covenants, terms and conditions of the
Agreement shall continue to be, and shall remain, in full force and effect in
accordance with its terms.

                  2.3 GOVERNING LAW. THIS AMENDMENT AND THE RIGHTS AND
OBLIGATIONS OF THE PARTIES HERETO SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF DELAWARE, WITHOUT GIVING EFFECT TO THE
CONFLICT OF LAW PRINCIPLES THEREOF.

                  2.4 COUNTERPARTS. This Amendment may be executed by one or
more of the parties on any number of separate counterparts, and all of said
counterparts taken together shall be deemed to constitute one and the same
instrument.



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                  2.5 DEPOSITOR ORDER. The Depositor hereby directs the Trustee,
not in its individual capacity but solely as Eligible Lender Trustee on behalf
of the Trust, to (1) execute and deliver this Amendment, the First Amendment to
the Sale and Servicing Agreement and the First Supplemental Indenture, each
dated as of the date hereof, (2) direct the Indenture Trustee to execute and
deliver the First Supplemental Indenture and undertake all of the actions set
forth therein, (3) execute and deliver a new Class M Note to replace the
existing Class M Note (and to instruct the Indenture Trustee to cancel and
destroy such old Class M Note), which contains the amendments set forth in
Paragraph 1.2 of the First Supplemental Indenture, and (4) to take such other
actions as are consistent with the transactions contemplated hereby.


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                           IN WITNESS WHEREOF, the parties hereto have caused
this Amendment to be duly executed and delivered by their respective proper and
duly authorized officers as of the day and year first above written.


                                KEY BANK USA, NATIONAL ASSOCIATION,
                                        as Depositor



                                By:/s/Darlene Dimitrijevs
                                   ------------------------------------
                                        Name:Darlene Dimitrijevs
                                        Title:Senior Vice President



                                BANK ONE, NATIONAL ASSOCIATION,
                                     not in its individual capacity but solely
                                     as Eligible Lender Trustee



                                By:/s/Jeffrey L. Kinney
                                   --------------------------------------
                                        Name:Jeffrey L. Kinney
                                        Title:Vice President



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CONSENTED AND AGREED TO:


KEY BANK USA, NATIONAL ASSOCIATION,
  as Cap Provider



By:/s/Darlene Dimitrijevs
   ------------------------------------
     Name: Darlene Dimitrijevs
     Title:Senior Vice President



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                      CONSENT BY INDIRECT BENEFICIAL OWNER

         The undersigned, an indirect beneficial owner of 99% of the issued and
outstanding Certificates, hereby consents to the foregoing Amendment and
represents and warrants that it is duly authorized to deliver this consent to
the Eligible Lender Trustee, and that such power has not been granted or
assigned to any other person.

Name of Indirect Beneficial Owner:     KEYBANK NATIONAL ASSOCIATION
                                  ----------------------------------------------
(Print Name of Authorized Signature):Craig T. Platt
Title: Senior Vice President
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Signature: /s/Craig T. Platt
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Address: 127 Public Square, Cleveland, Ohio 44114
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Phone: (216) 689-5608
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Fax: (216) 689-4579
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Date:    March 6, 2000
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                      CONSENT BY INDIRECT BENEFICIAL OWNER

         The undersigned, an indirect beneficial owner of 1% of the issued and
outstanding Certificates, hereby consents to the foregoing Amendment and
represents and warrants that it is duly authorized to deliver this consent to
the Eligible Lender Trustee, and that such power has not been granted or
assigned to any other person.

Name of Indirect Beneficial Owner:   KEY BANK USA, NATIONAL ASSOCIATION
                                  ----------------------------------------------
(Print Name of Authorized Signature):Craig T. Platt
Title: Senior Vice President
      --------------------------------------------------------------------------
Signature: /s/Craig T. Platt
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Address: 127 Public Square, Cleveland, Ohio 44114
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Phone: (216) 689-5608
      --------------------------------------------------------------------------
Fax: (216) 689-4579
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Date:    March 6, 2000
     ---------------------------------------------------------------------------




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                       CONSENT BY DIRECT BENEFICIAL OWNER

         The undersigned, the direct beneficial owner of 100% of the issued and
outstanding Certificates, hereby consents to the foregoing Amendment and
represents and warrants that it is duly authorized to deliver this consent to
the Eligible Lender Trustee, and that such power has not been granted or
assigned to any other person.

Name of Indirect Beneficial Owner: __CREDIT SUISSE FIRST BOSTON CORPORATION
                                  ----------------------------------------------
(Print Name of Authorized Signature): Joseph D. Fashano
Title: Director
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Signature: /s/Joseph D. Fashano
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Address: 11 Madison Avenue, New York, NY 10010
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Phone: (212) 325-2107
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Fax: (212) 325-8278
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Date:    March 6, 2000
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