Pen Friend Clubs of Japan is a program run by the Japanese Postal Service to match up Japanese junior high and senior high school students with overseas pen pals.
If you are a teacher in Japan, the applications page is in Japanese, but you can print out applications for individual students to fill out or applications for a whole class or club of students.
If you are a teacher overseas and want to find Japanese pen pals for your students, use an application from the English page.
In either case, send the completed application to:
Pen Friend Clubs of JapanPostage Stamps and Postcards Office
Mail Business Division
Japan Post Service Co., Ltd.
Tokyo 100-8798 JAPAN
The Japan Post Office will send a reply to the address listed as soon as they find a match for your student(s). The service is completely free.