SECOND AMENDMENT

Exhibit 10.18

SECOND AMENDMENT

SECOND AMENDMENT, dated as of August 8, 2006 (this “Second Amendment”), to the Amended and Restated Credit Agreement, dated as of April 28, 2005 (as amended, supplemented or otherwise modified, the “Credit Agreement”), among EDUCATE OPERATING COMPANY, LLC, a Delaware limited liability company (the “Borrower”), the several banks and other financial institutions or entities from time to time parties thereto (the “Lenders”), MERRILL LYNCH CAPITAL, a division of Merrill Lynch Business Financial Services Inc., as documentation agent (the “Documentation Agent”), and JPMORGAN CHASE BANK, N.A., as administrative agent (the “Administrative Agent”).

W I T N E S S E T H:

WHEREAS, the Borrower, the Lenders, the Documentation Agent and the Administrative Agent are parties to the Credit Agreement;

WHEREAS, the Administrative Agent has requested certain amendments to the Credit Agreement as set forth herein; and

WHEREAS, the Required Lenders have consented to the requested amendments as set forth herein;

NOW THEREFORE, in consideration of the premises and the mutual covenants hereinafter set forth, the parties hereto hereby agree as follows:

1. Defined Terms. Unless otherwise defined herein, capitalized terms used herein which are defined in the Credit Agreement are used herein as therein defined.

2. Amendments to Section 1. Section 1.1 of the Credit Agreement is hereby amended by inserting, in proper alphabetical order, the following new or substitute defined terms and related definitions:

“Applicable Margin”: (a) with respect to Revolving Loans, from and after the Second Amendment Effective Date, the rate per annum set forth under the relevant column heading in the grid below captioned “Revolving Loans Pricing Grid” and (b) with respect to Amended Term Loans, from and after the Second Amendment Effective Date, the rate per annum set forth under the relevant column heading in the grid below captioned “Amended Term Loans Pricing Grid.”

Revolving Loans Pricing Grid

Amended Term Loans Pricing Grid

For the purposes of the above pricing grids, changes to the Applicable Margin resulting from changes in the Consolidated Leverage Ratio shall become effective on the date that is three Business Days after the date on which financial statements are delivered to the Lenders pursuant to Section 6.1 and shall remain in effect until the next change to be effected pursuant to this paragraph. If any financial statements referred to above are not delivered within the time periods specified in Section 6.1, then, until the date that is three Business Days after the date on which such financial statements are delivered, the highest rate set forth in each column of the above pricing grid shall apply. In addition, at all times while an Event of Default shall have occurred and be continuing, the highest rate set forth in each column of the above pricing grid shall apply. Each determination of the Consolidated Leverage Ratio pursuant to the above pricing grid shall be made in a manner consistent with the determination thereof pursuant to Section 7.1.

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“Second Amendment”: the Second Amendment, dated as of August 8, 2006, to this Agreement.

“Second Amendment Effective Date”: August 8, 2006.

3. Amendment to Section 7 of the Credit Agreement. (a) Section 7.1(a) of the Credit Agreement is hereby amended by deleting the portion of the table set forth therein covering the fiscal quarters set forth below and substituting therefor the following:

(b) Section 7.1(b) of the Credit Agreement is hereby amended by deleting the portion of the table set forth therein covering the fiscal quarters set forth below and substituting therefor the following:

(c) Section 7.1(c) of the Credit Agreement is hereby amended by deleting the portion of the table set forth therein covering the fiscal quarters set forth below and substituting therefor the following:

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4. Conditions to Effectiveness of this Amendment. This Second Amendment shall become effective on and as of the date (such date the “Second Amendment Effective Date”) of the execution and delivery of this Second Amendment by the Borrower, the Administrative Agent and the Required Lenders and satisfaction of the following conditions precedent:

(a) The Administrative Agent shall have received payment, for distribution to each Lender that has signed and delivered this Second Amendment to the Administrative Agent by not later than 12:00 Noon (New York City time) on August 8, 2006 (or such later time or date as agreed by the Borrower and the Administrative Agent), of an amendment fee equal to 0.25% of the Aggregate Exposure of such Lender then in effect immediately prior to the Second Amendment Effective Date.

(b) The Lenders and the Administrative Agent shall have received all other fees required to be paid, and all expenses for which invoices have been presented (including the reasonable fees and expenses of legal counsel), in connection with the Second Amendment.

(c) The Administrative Agent shall have received (i) a certificate of the Secretary or Assistant Secretary or similar officer of the Borrower, dated the Second Amendment Effective Date, and certifying (A) that attached thereto is a true and complete copy of resolutions duly adopted by the Board of Directors (or equivalent governing body) of the Borrower (or its managing member) authorizing the execution, delivery and performance of this Second Amendment, and that such resolutions have not been modified, rescinded or amended and are in full force and effect on the Second Amendment Effective Date, (B) as to the incumbency and specimen signature of each officer executing this Second Amendment or any other document delivered in connection herewith on behalf of the Borrower and (C) as to the incumbency and specimen signature of the Secretary or Assistant Secretary or similar officer executing such certificate; and (ii) a good standing certificate for the Borrower from its jurisdiction of organization.

(d) The Administrative Agent shall have received an Acknowledgement and Consent in the form of Exhibit A attached hereto, executed and delivered by each Loan Party other than the Borrower.

5. Miscellaneous.

(a) Applicable Margin. Notwithstanding anything to the contrary in the Second Amendment or in any other Loan Documents, payment of interest and fees accrued during the period prior to the Second Amendment Effective Date shall be based upon the Applicable Margin in effect prior to the Second Amendment becoming effective.

(b) Representation and Warranties. The Borrower hereby represents that as of the Second Amendment Effective Date each of the representations and warranties made by any Loan Party in or pursuant to the Loan Documents is true and correct in all material respects as if made on and as of such date (it being understood and agreed that any representation or warranty that by its terms is made as of a specific date shall be required to be true and correct in all material respects only as of such specified date), and no Default or Event of Default has occurred and is continuing after giving effect to the amendments contemplated herein.

(c) Effect. Except as expressly amended hereby, all of the representations, warranties, terms, covenants and conditions of the Loan Documents shall remain unamended and not waived and shall continue to be in full force in effect.

(d) Counterparts. This Second Amendment may be executed by one or more of the parties to this Second Amendment on any number of separate counterparts, and all of said counterparts

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taken together shall be deemed to constitute one and the same instrument. A set of the copies of this Second Amendment signed by all the parties shall be lodged with the Borrower and the Administrative Agent.

(e) Severability. Any provision of this Second Amendment which is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction.

(f) Integration. This Second Amendment and the other Loan Documents represent the agreement of the Loan Parties, the Administrative Agent and the Lenders with respect to the subject matter hereof, and there are no promises, undertakings, representations or warranties by the Administrative Agent or any Lender relative to the subject matter hereof not expressly set forth or referred to herein or in the other Loan Documents.

(g) GOVERNING LAW. THIS SECOND AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES UNDER THIS SECOND AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

(h) Waiver. The Lenders waive any Default or Event of Default that may have occurred prior to the Second Amendment Effective Date as a result of the violation of Section 7.1 of the Credit Agreement, to the extent that such violation would not have occurred had this Second Amendment been effective as of June 30, 2006.

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IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment to be duly executed and delivered by their proper and duly authorized officers as of the day and year first above written.

Exhibit A

Form of Acknowledgement and Consent