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                                                                  EXHIBIT (A)(5)

                           OFFER TO PURCHASE FOR CASH
                           ALL SHARES OF COMMON STOCK
                                       OF
                     WAVE TECHNOLOGIES INTERNATIONAL, INC.
                                       AT

                              $9.75 NET PER SHARE
                                       BY

                          WTI ACQUISITION CORPORATION
                          A WHOLLY OWNED SUBSIDIARY OF

                            THE THOMSON CORPORATION

         THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT,
 NEW YORK CITY TIME, ON TUESDAY, APRIL 18, 2000, UNLESS THE OFFER IS EXTENDED.

To Our Clients:

     Enclosed for your consideration are an Offer to Purchase, dated March 22,
2000 (the "Offer to Purchase"), and a related Letter of Transmittal in
connection with the offer by WTI Acquisition Corporation, a Delaware corporation
("Purchaser") and a wholly owned subsidiary of The Thomson Corporation, a
corporation organized under the laws of Ontario, Canada ("Thomson"), to purchase
all outstanding shares of Common Stock, par value $0.50 per share (the
"Shares"), of Wave Technologies International, Inc., a Missouri corporation (the
"Company"), at a price of $9.75 per Share, net to the seller in cash, upon the
terms and subject to the conditions set forth in the Offer to Purchase, and in
the related Letter of Transmittal (which, together with any amendments or
supplements thereto, collectively constitute the "Offer").

     We (or our nominee) are the holder of record of Shares held by us for your
account. A tender of such Shares can be made only by us as the holder of record
and pursuant to your instructions. The Letter of Transmittal is furnished to you
for your information only and cannot be used by you to tender Shares held by us
for your account.

     We request instructions as to whether you wish to have us tender on your
behalf any or all of the Shares held by us for your account, upon the terms and
subject to the conditions set forth in the Offer.

     Your attention is invited to the following:

          1.  The tender price is $9.75 Share, net to the seller in cash.

          2.  The Offer is being made for any and all outstanding Shares.

          3.  The Board of Directors of the Company has determined that each of
     the Offer and the Merger (as defined in the Offer to Purchase) is fair to,
     and in the best interests of, the shareholders of the Company, and
     recommends that shareholders accept the Offer and tender their Shares
     pursuant to the Offer.

          4.  The Offer and withdrawal rights will expire at 12:00 Midnight, New
     York City time, on Tuesday, April 18, 2000, unless the Offer is extended.

          5.  The Offer is conditioned upon, among other things, there being
     validly tendered and not withdrawn prior to the expiration of the Offer at
     least two-thirds of the Shares outstanding on a fully diluted basis. The
     Offer is also conditioned upon, among other things, the expiration or
     termination of any applicable antitrust waiting period.
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          6.  Tendering shareholders will not be obligated to pay brokerage fees
     or commissions or, except as otherwise provided in Instruction 6 of the
     Letter of Transmittal, stock transfer taxes with respect to the sale and
     transfer of any Shares by Purchaser pursuant to the Offer.

     If you wish to have us tender any or all of your Shares, please so instruct
us by completing, executing and returning to us the instruction form contained
in this letter. An envelope in which to return your instructions to us is
enclosed. If you authorize the tender of your Shares, all such Shares will be
tendered unless otherwise specified in your instructions. Your instructions
should be forwarded to us in ample time to permit us to submit a tender on your
behalf prior to the expiration of the Offer.

     The Offer is made solely by the Offer to Purchase and the related Letter of
Transmittal and is being made to all holders of Shares. Purchaser is not aware
of any state where the making of the Offer is prohibited by administrative or
judicial action pursuant to any valid state statute. If Purchaser becomes aware
of any valid state statute prohibiting the making of the Offer or the acceptance
of Shares pursuant thereto, Purchaser will make a good faith effort to comply
with such state statute. If, after such good faith effort, Purchaser cannot
comply with such state statute, the Offer will not be made to (nor will tenders
be accepted from or on behalf of) the holders of Shares in such state. In any
jurisdiction where the securities, blue sky or other laws require the Offer to
be made by a licensed broker or dealer, the Offer shall be deemed to be made on
behalf of Purchaser by one or more registered brokers or dealers licensed under
the laws of such jurisdiction.

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                        INSTRUCTIONS WITH RESPECT TO THE
                           OFFER TO PURCHASE FOR CASH
                     ALL OUTSTANDING SHARES OF COMMON STOCK
                    OF WAVE TECHNOLOGIES INTERNATIONAL, INC.
                         BY WTI ACQUISITION CORPORATION

     The undersigned acknowledge(s) receipt of your letter and the enclosed
Offer to Purchase, dated March 22, 2000, and the related Letter of Transmittal
(which together constitute the "Offer") in connection with the offer by WTI
Acquisition Corporation, a Delaware corporation and a wholly owned subsidiary of
Thomson, a corporation organized under the laws of Ontario, Canada, to purchase
any and all outstanding shares of Common Stock, par value $0.50 per share (the
"Shares"), of Wave Technologies International, Inc., a Missouri corporation.

     This will instruct you to tender the number of Shares indicated below (or,
if no number is indicated below, all Shares) that are held by you for the
account of the undersigned, upon the terms and subject to the conditions set
forth in the Offer.

Number of Shares to be Tendered*:
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                                                                          SHARES
Date:
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                                   SIGN HERE

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SIGNATURE(S)

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PLEASE TYPE OR PRINT NAME(S)

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PLEASE TYPE OR PRINT ADDRESS

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AREA CODE AND TELEPHONE NUMBER

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TAXPAYER IDENTIFICATION OR SOCIAL SECURITY NUMBER

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* Unless otherwise indicated, it will be assumed that all Shares held by us for
  your account are to be tendered.

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