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                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                             ----------------------

                                   SCHEDULE TO

                  Tender Offer Statement Under Section 14(D)(1)

               Or 13(E)(1) of the Securities Exchange Act of 1934

                         CSI COMPUTER SPECIALISTS, INC.

                            (Name of Subject Company)

                                              -----------------------

                         Csi Computer Specialists, Inc.

                       (Name of Filing Person -- Offeror)

                    Common Stock, Par Value $0.001 Per Share

                        (Title of Classes of Securities)

                                                     12631103

                      (CUSIP Number of Class of Securities)

                                              -----------------------

                                Robert V. Windley

                         CSI Computer Specialists, Inc.

                         904 Wind River Lane, Suite 100

                          Gaithersburg, Maryland 63101

                                                  (301) 921-8860

     (Name, address and telephone number of person authorized to
    receive notices and communications on behalf of the person filing statement)

                                              -----------------------

                                 With a copy to:

                Denise R. Brown, Esq.
                     Shaw Pittman

                 2300 N Street, N.W.
                 Washington, DC 20037

                    (202) 663-8000

                            CALCULATION OF FILING FEE

               TRANSACTION VALUATION*                      AMOUNT OF FILING FEE

                          $2,520,888                               $504.18

   * Estimated for purposes of  calculating  the amount of filing fee only.  The
   amount  assumes the purchase of 2,520,888  shares of common stock,  par value
   $0.001 per share (the "Common Shares"),  at a price per Common Share of $1.00
   cash.  Such number of Common Shares  represents  the fully diluted  number of
   Common  Shares  outstanding  as of April 24, 2000,  less the number of Common
   Shares  already  beneficially  owned by Mr.  Donald  C.  Weymer,  Interactive
   Systems,  Inc.'s  Chief  Executive  Officer,  President,  a Director  and 98%
   shareholder.

       [ ] Check  box if any  part  of the fee is  offset  as  provided  by Rule
       0-11(a)(2)  and  identify  the filing with which the  offsetting  fee was
       previously paid.  Identify the previous filing by registration  statement
       number, or the Form or Schedule and the date of its filing.

       Amount Previously Paid:  None.               Filing Party: Not Applicable
       Form or Registration No.:  Not applicable.   Date Filed:  Not applicable.

       [  ]  Check  the  box  if  the  filing   relates  solely  to  preliminary
       communications made before the commencement of a tender offer.

       Check the appropriate  boxes below to designate any transactions to which
the statement relates:

       [X] third-party tender offer subject to Rule 14d-1.

       [ ]  issuer tender offer subject to Rule 13e-4.

       [ ]  going-private transaction subject to Rule 13e-3.

       [ ]  amendment to Schedule 13D under Rule 13d-2.

               Check  the  following  box if the  filing  is a  final  amendment
               reporting the results of the tender offer: [ ]








                                                       - 4 -

       This  Tender  Offer  Statement  on  Schedule  TO is filed by  Interactive
       Systems, Inc. ("ISI"), an affiliate of CSI Computer Specialists, Inc. The
       Schedule  TO  relates  to the offer by ISI to  purchase  all  outstanding
       shares of Common Stock, par value $0.001 per share (the "Common Shares"),
       of CSI Computer  Specialists,  Inc.  (the  "Company") at $1.00 per Common
       Share, net to the seller in cash (less any required  withholding  taxes),
       upon the terms and  subject to the  conditions  set forth in the offer to
       purchase  (the  "Offer  to  Purchase")  and  in  the  related  letter  of
       transmittal (the "Letter of  Transmittal,"  which together with the Offer
       to Purchase,  as amended or supplemented from time to time,  collectively
       constitute the "Offer"),  attached  hereto as Exhibits (a)(1) and (a)(2),
       respectively.  The  information  set forth in the  Offer is  incorporated
       herein by reference with respect to Items 1-9, 11 and 13 of Schedule TO.

ITEM 10.  FINANCIAL STATEMENTS OF CERTAIN BIDDERS.

       ISI believes that its financial  statements  are immaterial to a decision
       as to whether to tender  Common  Shares in the Offer because (a) the only
       consideration offered for the Common Shares is cash; (b) the Offer is not
       subject to any financing  condition;  and (c) the Offer is for all of the
       outstanding  Common Shares not already owned by Mr. Donald C. Weymer, the
       founder,   Chief  Executive  Officer,   President,  a  Director  and  98%
       shareholder of ISI.

ITEM 12.  EXHIBITS.

            (a)(1)    Offer to Purchase dated April 26, 2000.

            (a)(2)    Form of Letter of Transmittal.

            (a)(3)    Form of Notice of Guaranteed Delivery.

            (a)(4)    Form of Letter to Brokers, Dealers, Commercial Banks,
                      Trust Companies and Other Nominees.

            (a)(5)    Form of Letter to Clients for use by Brokers, Dealers,
                      Commercial Banks, Trust Companies and Other Nominees.

            (a)(6)    Text  of  press  release  jointly  issued  by ISI  and the
                      Company dated April 26, 2000.

               (a)(7)  Guidelines for  Certification of Taxpayer  Identification
               Number on Substitute Form W-9.

            (b)(1)     Amended and Restated Loan and Security  Agreement between
                       ISI and Sandy Spring  National Bank, for $4,000,000  Line
                       of Credit,  dated March 30, 2000, and Related  Promissory
                       Note.

            (b)(2) Letter of Consent between ISI and Sandy Spring National Bank,
dated April 24, 2000.

            (g)       None.

            (h)       None.





                                    SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the
information set forth in this statement is true, complete and correct.

                                                    INTERACTIVE SYSTEMS, INC.

                                      By /s/ DONALD C. WEYMER

                                   Name:     Donald C. Weymer
                                  Title:   President and Chief Executive Officer

Dated: April 26, 2000





                                  EXHIBIT INDEX

            (a)(1)    Offer to Purchase dated April 26, 2000.

            (a)(2)    Form of Letter of Transmittal.

            (a)(3)    Form of Notice of Guaranteed Delivery.

            (a)(4)    Form of Letter to Brokers, Dealers, Commercial Banks,
                      Trust Companies and Other Nominees.

            (a)(5)    Form of Letter to Clients for use by Brokers, Dealers,
                      Commercial Banks, Trust Companies and Other Nominees.

            (a)(6)    Text  of  press  release  jointly  issued  by ISI  and the
                      Company dated April 26, 2000.

               (a)(7)  Guidelines for  Certification of Taxpayer  Identification
               Number on Substitute Form W-9.

            (b)(1)     Amended and Restated Loan and Security  Agreement between
                       ISI and Sandy Spring  National Bank, for $4,000,000  Line
                       of Credit,  dated March 30, 2000, and Related  Promissory
                       Note.

            (b)(2) Letter of Consent between ISI and Sandy Spring National Bank,
dated April 24, 2000.

            (g)       None.

            (h)       None.