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                                                                   Exhibit 10.28

                               FIRST AMENDMENT OF
                   MARKETING EXPENSE REIMBURSEMENT AGREEMENT

                  This First Amendment of Marketing Expense Reimbursement
         Agreement (the "Amendment") is made and entered into as of this 1st day
         of April, 2001, by and between Union Bank and Trust Company, a Nebraska
         bank and trust company, acting in its own right and in its capacity as
         trustee ("Union Bank") and NELnet, Inc., a Nevada corporation f/k/a
         National Education Loan Network, Inc. ("NELnet").

                  WHEREAS, the parties hereto entered into that certain
         Marketing Expense Reimbursement Agreement dated as of January 1, 1999
         (the "Agreement"), and the parties hereto wish to amend the Agreement
         under the terms set forth herein.

                  NOW, THEREFORE, in consideration of the foregoing premises
         and the mutual covenants herein contained, the parties hereto agree as
         follows:

                  1.       Definitions. Unless otherwise expressly stated
         herein, capitalized terms in this Amendment shall have the same
         meanings given to them in the Agreement.

                  2.       Reduction of Services to Be Provided by Union Bank.
         Notwithstanding provisions to the contrary contained in Section 1 of
         the Agreement, Union Bank may, at its option, and in its sole
         discretion, reduce its Student Loan and Alternative Loan marketing and
         origination efforts as compared to historic levels of such efforts by
         reducing its marketing personnel commitment. Union Bank agrees that if
         it reduces its marketing personnel commitment, it shall enable NELnet
         to offer employment to such personnel and, at NELnet's reasonable
         request, continue such personnel as dual employees of NELnet and Union
         Bank provided, however, that such personnel shall not be entitled to
         any salary paid by Union Bank or Union Bank employee benefits. NELnet
         shall provide nonexclusive marketing and promotional services with
         respect to Student Loans originations under the Union Bank brand name
         in the states of Nebraska, Kansas, Iowa and portions of the western
         region of the United States where the Union Bank brand name is
         currently used to market Student Loans (including Arizona, California,
         Oregon, Washington and Hawaii), at least at historic levels previously
         furnished by Union Bank itself in those states, or as the parties may
         otherwise mutually agree; provided, however, that NELnet shall not
         provide such services with respect to Student Loans to borrowers (other
         than medical students) attending University of Phoenix or Loma Linda
         College unless Union Bank ceases origination efforts at such
         educational institutions or otherwise consents to such services being
         provided by NELnet.

                  3.       Reimbursement of Marketing Costs. Section 3 of the
         Agreement shall be deleted in its entirely and the following
         substituted in lieu thereof;

                  "Marketing Costs" as defined herein shall mean all direct
                  costs and expenses during the term of this Agreement, in
                  connection with or arising from marketing activities by Union
                  Bank and NELnet relating to Student Loans, excluding any
                  administrative or overhead costs and expenses associated
                  therewith, and, following April 1, 2001, excluding any costs
                  for marketing representatives and related expenses arising
                  from

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                  Student Loan activities in the northeastern region of the
                  United States (including, without limitation, New York, New
                  Jersey, Connecticut, Pennsylvania, Vermont, New Hampshire and
                  Maine) as well as the states of Illinois, South Dakota,
                  Minnesota, Texas and Colorado. Marketing Costs incurred with
                  respect to the states of Nebraska, Kansas, Iowa and portions
                  of the western region of the United States where the brand
                  name of Union Bank is currently used to market Student Loans
                  (including Arizona, California, Oregon, Washington and Hawaii)
                  shall be included in the computation of Marketing Costs.
                  NELnet and Union Bank shall each be responsible for their
                  respective pro rata share of Marketing Costs during each
                  calendar year during the term of this Agreement, and each
                  party's respective share shall be calculated based upon the
                  following formulas:

A. NELnet's annual = All annual Marketing Costs X ($120 million - 75% of annual
       share of      Union Bank originations in excess of $240 Million)/
   Marketing Costs   All Union Bank Student Loan Originations for the year


B.       Union Bank's share of Marketing Costs = all Marketing Costs for the
         year minus NELnet's share of Marketing Costs as calculated pursuant to
         (A) above.

         Union Bank hereby transfers all of its rights and interest in certain
         software products utilized in connection with Student Loans, including
         without limitation "EnConcert," "Notes on Student Loans," "Notes on
         Credit," "Notes on Investments," "Union Station," and "Student
         Exchange" (collectively, the "Student Loan Software"). Union Bank shall
         take all reasonable acts necessary to effectuate such transfer as
         reasonably requested by NELnet. NELnet shall assume responsibility for
         any future enhancements or development of the Student Loan Software.
         NELnet shall reimburse Union Bank and its affiliates for any expense in
         connection with Alternative Loans originated after January 1, 2000. It
         is acknowledged that NELnet is providing substantial consideration by
         assuming a greater share of Marketing Expenses such as salary expenses
         related to hiring of marketing personnel, marketing expenses related to
         Alternative Loans, software development expenses related to EnConcert
         and other intellectual property development, and access granted by
         NELnet to Union Bank to all future enhancements to the EnConcert
         software or modifications thereof.

                  4.       Origination Fees. Union Bank shall amend origination
         services agreements with NELnet or any affiliate thereof in order to
         adjust origination fees to the market rate of $25 per Student Loan,
         effective April 1, 2001,

                  5.       Effect of Amendment. Unless expressly modified or
         amended by this Amendment, all terms and provision contained in the
         Agreement shall remain in full force and effect without modification.

         Union Bank and Trust Company           NELnet, Inc.

         By: /s/ Mike Dunlap                    By: /s/ Don Bouc
             ------------------------               -------------------------
         Title: CEO                             Title: President

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