UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 8)*

Learning Tree International, Inc.

(Name of Issuer)

Common Stock, $0.0001 par value

(Title of Class of Securities)

522015106

(CUSIP Number)

Mill Road Capital II, L.P.

Attn: Thomas E. Lynch

382 Greenwich Avenue

Suite One

Greenwich, CT 06830

203-987-3500

With a copy to:

Peter M. Rosenblum, Esq.

Foley Hoag LLP

155 Seaport Blvd.

Boston, MA 02210

617-832-1151

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 10, 2015

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ¨

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

13D

13D

13D

13D

This Amendment No. 8 to the joint statement on Schedule 13D with respect to the common stock, $0.0001 par value (the “Common Stock”), of Learning Tree International, Inc., a Delaware corporation (the “Issuer”), filed by Thomas E. Lynch, Scott P. Scharfman, Mill Road Capital II GP LLC, a Delaware limited liability company, and Mill Road Capital II, L.P., a Delaware limited partnership (each of the foregoing filers is referred to herein as a “Reporting Person” and, collectively, as the “Reporting Persons”), as well as other persons reporting on such joint statement, as amended and restated by the Amendment No. 7 on Schedule 13D with respect to the Common Stock filed by the Reporting Persons on June 22, 2015 (such filing, as so amended and restated and as amended herein, the “Schedule 13D”), amends the Schedule 13D as follows:

1. Item 4 of the Schedule 13D is amended by inserting the following paragraph after its fourth paragraph:

“On September 10, 2015, the Management Company sent the letter attached hereto as Exhibit 6 to the Issuer’s board of directors, indicating its interest in consummating a going private transaction at a purchase price of $1.80 per share.”

2. Item 7 of the Schedule 13D is amended by adding the following paragraph at its end:

3. Except as amended hereby, the Schedule 13D remains in full force and effect.

Signature

After reasonable 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.

Exhibit 6

PRIVATE & CONFIDENTIAL

September 10, 2015

Board of Directors

Learning Tree International, Inc.

1831 Michael Faraday Drive

Reston, VA 20190

Re: Mill Road Capital Indication of Interest to Take Learning Tree Private at $1.80 Per Share

Members of the Board of Directors:

The private equity funds advised by Mill Road Capital Management, LLC (“Mill Road”) have been a shareholder of Learning Tree International, Inc. (“Learning Tree” or the “Company”) since 2009. Since then, we have given several indications of interest regarding leading a going private transaction and continue to believe that a sale of the Company is in the best interest of shareholders, particularly in light of the delisting of the Company’s shares from the NASDAQ Global Market.

We have committed substantial time and effort to understanding Learning Tree, both as a public shareholder and as a participant in the transaction process organized by the Board of Directors in the summer of 2011. We continue to have a serious interest in consummating a going private transaction, the key terms of which would be:

382 Greenwich Avenue, Suite One ● Greenwich, CT 06830 ● (203) 987-3500

This indication of interest is non-binding. Any binding obligations will be created only by execution and delivery of definitive documents.

Additionally, we would like to acknowledge the amended and supplemented Item 4 provided in the amended 13D filing made by Dr. David C. Collins on May 19, 2015. We acknowledge the Board’s request that Dr. Collins consider purchasing all the remaining shares of stock of the Company. If Dr. Collins does not support our proposed transaction and elects to purchase all remaining shares, Mill Road could support such a transaction as long as this purchase provides full and fair consideration for the selling shareholders.

We look forward to hearing from you. You may reach me at (203) 987-3505.

Sincerely,

Mill Road Capital Management, LLC