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                                                                 Exhibit 10.3

                 AMENDMENT NO. 1 TO AGREEMENT AND PLAN OF MERGER


Amendment No. 1 to Agreement and Plan of Merger, dated as of August 4, 2000
(this "AMENDMENT"), to the Agreement and Plan of Merger, dated as of July 30,
2000 (the "MERGER AGREEMENT") among Pearson plc, a public limited company
registered in England and Wales, PN Acquisition Subsidiary Inc., a Minnesota
corporation and National Computer Systems, Inc., a Minnesota corporation.

WHEREAS, the parties desire to amend the Merger Agreement in certain respects.

NOW, THEREFORE, the parties hereto hereby agree as follows:

SECTION 1.  AMENDMENTS TO MERGER AGREEMENT.

         (a) The third sentence of Section 1.01(a) of the Merger Agreement is
hereby deleted in its entirety and replaced with:

         "The initial expiration date of the Offer shall be the 23rd business
         day following the date on which the Offer is commenced."

         (b) Clause (C) of Section 1.01(a) of the Merger Agreement shall be
deleted in its entirety and replaced with:

         "(C) extend the Offer for an aggregate period of not more than 17
business days beyond the initial expiration date of the Offer to the extent
required by Parent to enable Parent and Sub to complete the financing of the
purchase of shares of Company Common Stock tendered pursuant to the Offeror"

SECTION 2. MISCELLANEOUS. Except as and to the extent expressly modified by this
Amendment, the Merger Agreement (including all exhibits thereto) shall remain in
full force and effect in all respects. This Amendment shall be governed by, and
construed in accordance with, the laws of the State of Minnesota. This Amendment
may be executed in one or more counterparts, and by the different parties hereto
in separate counterparts, each of which when executed shall be deemed to be an
original but all of which taken together shall constitute one and the same
agreement. Delivery of an executed counterpart of a signature page to this
Amendment by telecopier shall be effective as delivery of a manually executed
counterpart of this Amendment.


                            [SIGNATURE PAGE FOLLOWS.]
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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed
as of the date first written above by their respective officers thereunto duly
authorized.


                                        PEARSON PLC


                                        By: /s/ Marjorie Scardino
                                            ---------------------
                                            Name: Marjorie Scardino
                                            Title: Chief Executive


                                        PN ACQUISITION SUBSIDIARY INC.


                                        By: /s/ Robert Dancy
                                            ----------------
                                            Name: Robert Dancy
                                            Title: Vice President


                                        NATIONAL COMPUTER SYSTEMS, INC.


                                        By: /s/ Russell A. Gullotti
                                            -----------------------
                                            Name: Russell A. Gullotti
                                            Title: Chairman, President and
                                                   Chief Executive Officer



        Signature page to Amendment No. 1 to Agreement and Plan of Merger