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                                 EXHIBIT 10.18


                         NATIONAL EDUCATION CORPORATION

                                SECOND AMENDMENT
                              TO CREDIT AGREEMENT


                 This SECOND AMENDMENT TO CREDIT AGREEMENT (this "Amendment")
is dated as of December 21, 1995 and entered into by and among National
Education Corporation, a Delaware corporation (the "Borrower"), the Bank listed
on the signature pages hereof (the "Bank"), and Bankers Trust Company, as agent
for the Bank (the "Agent") and, for purposes of Sections 3 and 4 hereof, the
Subsidiaries of the Borrower listed on the signature pages hereof, and is made
with reference to that certain Amended and Restated Credit Agreement dated as
of February 28, 1995 by and among the Borrower, the Bank and the Agent, as
amended by that certain First Amendment and Limited Waiver to Credit Agreement
dated as of August 4, 1995 (as so amended, the "Credit Agreement"). Capitalized
terms used herein without definition shall have the same meanings herein as set
forth in the Credit Agreement.

                                    RECITALS

                 WHEREAS, the Borrower and the Bank have agreed, upon the terms
and conditions set forth herein, that the term of the Credit Agreement should
be extended from December 21, 1995 to January 16, 1996; and

                 WHEREAS, each of the Subsidiaries of the Borrower party to the
Subsidiary Guaranty ("Subsidiary Guarantors") or the Subordination Agreement
("Subordinated Subsidiaries") desires to acknowledge and consent to this
Amendment and to reaffirm the continuing effectiveness of the Subsidiary
Guaranty or the Subordination Agreement, as the case may be;

                 NOW, THEREFORE, in consideration of the foregoing and the
mutual covenants and agreements set forth herein, the parties hereto agree as
follows:

                 SECTION 1. AMENDMENTS TO THE CREDIT AGREEMENT

                 1.1      AMENDMENT TO SECTION 1.01: DEFINED TERMS.

                 Section 1.01 of the Credit Agreement is hereby amended by
amending and restating the definition of "Termination Date" as follows:





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                 "'Termination Date' shall mean the earlier of (a) January 16,
         1996 and (b) the date upon which the Revolving Loan Commitments are
         terminated pursuant to subsection 4.06 or Section 9."

                 SECTION 2. CONDITIONS TO EFFECTIVENESS

                 The amendment to the Credit Agreement set forth in Section 1
hereof shall become effective as of the date hereof upon the Borrower's, the
Bank's, each Subsidiary Guarantor's and each Subordinated Subsidiary's
execution and delivery of counterparts hereof provided the Agent shall have
received the following, in each case in form and substance satisfactory to the
Agent:

                 (i) copies of resolutions of the Borrower, each Subsidiary
         Guarantor and each Subordinated Subsidiary approving and authorizing
         the execution and delivery of this Amendment by such Person and the
         Borrower's performance of the Credit Agreement, as amended by this
         Amendment, in each case certified by such Person's secretary or
         assistant secretary as being in full force and effect and as
         constituting all action by such Person with respect to this Amendment
         and the extension of the term of the Credit Agreement contemplated
         hereunder.

                 (ii) An allonge to the Note, substantially in the form of
         Annex 1 to this Amendment, executed by the Borrower.

                 SECTION 3. REPRESENTATIONS AND WARRANTIES

                 In order to induce the Bank to enter into this Amendment and
to amend the provisions of the Credit Agreement in the manner provided herein,
the Borrower, and each Subsidiary party to the Subsidiary Guaranty and/or the
Subordination Agreement with respect to itself only, represents and warrants to
the Bank that the following statements are true, correct and complete:

                 A.       CORPORATE POWER AND AUTHORITY. The Borrower has all
requisite corporate power and authority to enter into this Amendment and to
carry out the transactions contemplated by, and perform its obligations under,
the Credit Agreement as amended by this Amendment (the "Amended Agreement").
Each such Subsidiary has all requisite corporate power and authority to enter
into this Amendment and to be bound hereby.

                 B.       AUTHORIZATION OF AGREEMENTS. The execution and
delivery of this Amendment by the Borrower and each such Subsidiary and the
performance of the Amended Agreement by the Borrower have been duly authorized
by all necessary corporate





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action by the Borrower and each such Subsidiary, as the case may be.

                 C.       NO CONFLICT. The execution and delivery by the
Borrower and each such Subsidiary of this Amendment and the performance by the
Borrower of the Amended Agreement do not and will not (i) violate any provision
of any law, rule or regulation applicable to the Borrower or any of its
Subsidiaries, the Certificate of Incorporation or Bylaws of the Borrower or any
of its Subsidiaries or any order, judgment or decree of any court or other
agency of government binding on the Borrower or any of its Subsidiaries, (ii)
conflict with, result in a breach of or constitute (with due notice or lapse of
time or both) a default under, or require the consent of any Person under, any
mortgage, deed of trust, credit agreement, loan agreement or any other
agreement contract or instrument to which the Borrower or any of its
Subsidiaries is a party or by which it or any of its property or assets is
bound or to which it may be subject or (iii) result in or require the creation
or imposition of any Lien upon any of their properties or assets.

                 D.       GOVERNMENTAL CONSENTS. The execution and delivery by
the Borrower and each such Subsidiary of this Amendment and the performance by
the Borrower of the Amended Agreement do not and will not require any
registration with, consent or approval of, or notice to, or other action to,
with or by, any Federal, state or other governmental authority or regulatory
body or other Person.

                 E.       BINDING OBLIGATION. This Amendment and, in the case
of the Borrower, the Amended Agreement, are the legally valid and binding
obligation(s) of the Borrower and each such Subsidiary, enforceable against the
Borrower or such Subsidiary in accordance with its terms, except as enforcement
may be limited by bankruptcy, insolvency, reorganization, moratorium or other
similar laws relating to or limiting creditors' rights generally or by
equitable principles relating to enforceability.

                 F.       INCORPORATION OF REPRESENTATIONS AND WARRANTIES FROM
CREDIT AGREEMENT. The representations and warranties contained in Section 6 of
the Credit Agreement are and will be true, correct and complete in all material
respects on and as of the date hereof to the same extent as though made on and
as of that date, except to the extent that such representations and warranties
specifically relate to an earlier date, in which case they are true, correct
and complete in all material respects as of such earlier date.

                 G.       ABSENCE OF DEFAULT. Upon giving effect to this
Amendment, no event has occurred and is continuing or will result from the
consummation of the transactions contemplated by this





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Amendment which would constitute an Event of Default or a Default.


                 SECTION 4.       ACKNOWLEDGEMENT AND CONSENT

                 Each of the undersigned Subsidiaries of the Borrower
acknowledges that it has reviewed the terms and provisions of the Credit
Agreement and this Amendment and consents to the amendment of the Credit
Agreement effected pursuant to this Amendment. Each of the undersigned
Subsidiary Guarantors hereby confirms that the Subsidiary Guaranty will
continue to guaranty to the fullest extent possible the payment and performance
of all Guarantied Obligations (as defined in~-the Subsidiary Guaranty),
including, without limitation, the payment and performance of all Obligations
of the Borrower now or hereafter existing under or in respect of the Amended
Agreement. Each of the undersigned Subordinated Subsidiaries hereby confirms
that the Subordination Agreement will continue to subordinate the Subordinated
Debt (as defined in the Subordination Agreement) to Senior Obligations (as
defined in the Subordination Agreement), including, without limitation, all
obligations of the Borrower now or hereafter existing to make payments under or
in respect of the Amended Agreement.

                 Each Subsidiary Guarantor acknowledges and agrees that the
Subsidiary Guaranty shall continue in full force and effect and that all of its
obligations thereunder shall be valid and enforceable and shall not be impaired
or affected by the execution or effectiveness of this Amendment. Each
Subsidiary Guarantor represents and warrants that all representations and
warranties contained in the Subsidiary Guaranty are true, correct and complete
in all material respects on and as of the date hereof to the same extent as
though made on and as of that date except to the extent that such
representations and warranties specifically relate to an earlier date, in which
case they are true, correct and complete in all material respects as of such
earlier date.

                 Each Subordinated Subsidiary acknowledges and agrees that the
Subordination Agreement shall continue in full force and effect and that all of
its obligations thereunder shall be valid and enforceable and shall not be
impaired or affected by the execution or effectiveness of this Amendment. Each
Subordinated Subsidiary represents and warrants that all representations and
warranties contained in the Subordination Agreement are true, correct and
complete in all material respects on and as of the date hereof to the same
extent as though made on and as of that date except to the extent that such
representations and warranties specifically relate to an earlier date, in which
case





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they are true, correct and complete in all material respects as of such earlier
date.

                 Each of the undersigned Subsidiaries of the Borrower
acknowledges and agrees that (i) notwithstanding the conditions to
effectiveness set forth in this Amendment, such

Subsidiary is not required by the terms of the Credit Agreement or any other
Credit Document to consent to the amendments to the Credit Agreement effected
pursuant to this Amendment and (ii) nothing in the Credit Agreement, this
Amendment or any other Credit Document shall be deemed to require the consent
of any such Subsidiary to any future amendments to the Credit Agreement.

                 SECTION 5. MISCELLANEOUS

                 A.       REFERENCE TO AND EFFECT ON THE CREDIT AGREEMENT AND
THE OTHER CREDIT DOCUMENTS.

                          (i)     On and after the date hereof, each reference
         in the Credit Agreement to "this Agreement", "hereunder", "hereof",
         "herein" or words of like import referring to the Credit Agreement,
         and each reference in the other Credit Documents to the "Credit
         Agreement", "thereunder", "thereof" or words of like import referring
         to the Credit Agreement shall mean and be a reference to the Credit
         Agreement as amended by this Amendment.

                          (ii)    Except as specifically amended or modified by
         this Amendment, the Credit Agreement and the other Credit Documents
         shall remain in full force and effect and are hereby ratified and
         confirmed.

                          (iii) The execution, delivery and performance of this
         Amendment shall not, except as expressly provided herein, constitute a
         waiver of any provision of, or operate as a waiver of any right, power
         or remedy of the Agent or any Bank under, the Credit Agreement or any
         of the other Credit Documents.

                 B.       FEES AND EXPENSES. The Borrower acknowledges that all
costs, fees and expenses as described in subsection 11.01 of the Credit
Agreement incurred by the Agent and its counsel with respect to this Amendment
and the documents and transactions contemplated hereby shall be for the account
of the Borrower.

                 C.        EXECUTION IN COUNTERPARTS. This Amendment may be
executed in any number of counterparts, and by different parties hereto in
separate counterparts, each of which when so executed and delivered shall be
deemed an original, but all such





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counterparts taken together shall constitute but one and the same instrument.

                 D.       EFFECTIVENESS. This Amendment shall become effective
as of the date hereof upon the execution of a counterpart hereof by the
Borrower, each Subsidiary of the Borrower party to the Subsidiary Guaranty or
the Subordination Agreement and the Bank and the delivery of such counterparts 
to the Agent; provided, however, that the amendment to the Credit Agreement 
set forth in Section 1 this Amendment shall not be effective until the 
conditions set forth in Section 2 of this Amendment are satisfied.

                 E.       HEADINGS. Section and subsection headings in this
Amendment are included herein for convenience of reference only and shall not
constitute a part of this Amendment for any other purpose or be given any
substantive effect.

                 F. APPLICABLE LAW. THIS AMENDMENT AND THE RIGHTS AND
OBLIGATIONS OF THE PARTIES HERETO AND ALL OTHER ASPECTS HEREOF SHALL BE DEEMED
TO BE MADE UNDER, SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED IN
ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK.

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                 IN WITNESS WHEREOF, the parties hereto have caused this
Amendment to be executed as of the date first above written by their respective
officers "hereunto duly authorized.



                                   NATIONAL EDUCATION CORPORATION


                                   By: 
                                       --------------------------------
                                   Title: 
                                          -------------------------------



                                   NETG HOLDING, INC.
                                   NATIONAL EDUCATION TRAINING GROUP, INC.,
                                   SPECTRUM INTERACTIVE
                                        INCORPORATED
                                   NATIONAL EDUCATION CENTERS, INC.
                                   ICS LEARNING SYSTEMS, INC.
                                   INTERNATIONAL CORRESPONDENCE
                                        SCHOOLS, INC.,
                                   AS THE SUBSIDIARY GUARANTORS


                                   By: 
                                       --------------------------------
                                   Title: 
                                          -------------------------------





                                   NATIONAL EDUCATION INTERNATIONAL
                                        CORP.
                                   NATIONAL EDUCATION CREDIT
                                        CORPORATION
                                   NATIONAL EDUCATION FOREIGN SALES
                                        CORP.
                                   NATIONAL EDUCATION PAYROLL CORP.
                                   NATIONAL EDUCATION CENTERS, INC.
                                   ICS LEARNING SYSTEMS, INC.
                                   NETG HOLDING, INC.,
                                   AS THE SUBORDINATED SUBSIDIARIES


                                   By: 
                                       --------------------------------
                                   Title: 
                                          -------------------------------



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                                   BANKERS TRUST COMPANY, AS THE
                                   BANK AND AS THE AGENT


                                   By: 
                                       --------------------------------
                                   Title: 
                                          -------------------------------
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                        ALLONGE DATED DECEMBER 21, 1995
                   TO PROMISSORY NOTE DATED FEBRUARY 28, 1995



                 This Allonge amends, and is to be affixed to so as to become
part of, that certain Promissory Note dated February 28, 1995, in the principal
amount of $13,500,000, by the undersigned National Education Corporation, as
the Borrower, to Bankers Trust Company, as the Payee (the "Note").

                 The Note is hereby amended by deleting the date December 21,
1995, from the first paragraph thereof and substituting therefor the date
January 16, 1996.

                 In witness whereof, the Borrower and the Payee have caused
this Allonge to be executed and delivered by their duly authorized officers.


Dated: December 21, 1995

                                        NATIONAL EDUCATION CORPORATION



                                        By: 
                                            ------------------------------
                                        Title: 
                                               -----------------------------

                                        BANKERS TRUST COMPANY


                                        By: 
                                            ------------------------------
                                        Title: 
                                               -----------------------------