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                                                                    Exhibit 3.1

                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                                   ACTV, INC.

                                    * * * * *


               ACTV, Inc., a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware, DOES HEREBY
CERTIFY:

               FIRST: That at a meeting of the Board of Directors of ACTV, Inc.
(the "Corporation"), resolutions were duly adopted setting forth a proposed
amendment to the Restated Certificate of Incorporation of the Corporation,
declaring said amendment to be advisable and calling an annual meeting of the
stockholders of the Corporation for consideration of, among other things, said
amendment. The resolution setting forth the proposed amendment is as follows:

               RESOLVED, that the Company's Restated Certificate of
               Incorporation be amended by deleting the first paragraph of
               Article IV of the Restated Certificate of Incorporation of the
               Company in its entirety and substituting in lieu thereof the
               following:

                             "FOURTH: (A) The aggregate number of shares of all
                             classes of stock which the corporation shall have
                             authority to issue is THIRTY-SIX MILLION
                             (36,000,000) shares, divided into classes as
                             follows:

                             (1) THIRTY-FIVE MILLION (35,000,000) shares of
                      Common Stock, $0.10 per share (hereinafter called the
                      "Common Stock"); and

                             (2) ONE MILLION (1,000,000) shares of Preferred
                      Stock, $0.10 per share (hereinafter called the "Preferred
                      Stock"), to be issued in series;" and it is further


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                      RESOLVED, that except as expressly amended, the Fourth
               Article of the Restated Certificate of Incorporation of the
               Corporation shall hereby remain in effect as heretofore set forth
               and shall be unchanged in any respect by any provision thereof.

               SECOND: That thereafter, pursuant to resolution of its Board of
Directors, an annual meeting of the stockholders of the Corporation was duly
called and held, upon notice in accordance with Section 222 of the General
Corporation Law of the State of Delaware at which meeting the necessary number
of shares as required by statute were voted in favor of the amendment.

               THIRD: That said amendment was duly adopted in accordance with
the provisions of Section 242 of the General Corporation Law of the State of
Delaware.

               FOURTH: That the capital of the Corporation shall not be reduced
under or by reason of said amendment.

               IN WITNESS WHEREOF, the Corporation has caused this certificate
to be signed by William C. Samuels, its Chief Executive Officer and President
and attested to by Christopher C. Cline, its Secretary, this 31st day of July,
1996.

                                       By: /s/ William C. Samuels
                                       Chief Executive Officer and President

ATTEST:

By: /s/ Christopher Cline
        Secretary


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