Theatre can be a great way to hone the artistic and collaborative talents of young people in a community. Unfortunately, most plays require the performers to pay for the rights to practice, promote, and perform them. However, this page from Ohio Wesleyan University contains scripts that are in the public domain, meaning anyone can use them for any reason at any time. These plays, though usually older, are often classics and could prove great resources for young changemakers looking to introduce their communities to the theatre.
Pro-tip: I especially recommend Trifles by Susan Glaspell, A Doll's House by Henrick Ibsen, Candida by George Bernard Shaw, or The Importance of Being Earnest by Oscar Wilde.