A good project for teenagers (both LDS Church members and also their friends and neighbors) is SYI, Summer Youth Indexing. It is as fun and more fulfilling and productive than computer games they may play this summer.
www.FamilySearchIndexing.org provides opportunity to learn about primary and secondary documents. They learn by indexing. Young Men and Young Women advisors should volunteer for Indexing so they can lead youth in summer righteousness. As they go to Temples for baptism for the dead (ancestors, yours and mine) they appreciate this holy work more after experiencing Indexing. Give it a try.
We are very, very interested in exchanging success stories and tips in the area of Summer Youth Indexing!