Freethought Books Project: Volunteer, Donate

"The Freethought Books Project provides donations of secular and freethinking literature to prisoners, inmates in mental hospitals, books to prisoners projects, and others in need. The program also connects inmates to volunteer pen pals, who correspond with secular humanist, atheist, and other inmates who are connected to the project. This project has been administered by the Center for Inquiry since 2013..."

http://www.centerforinquiry.net/outreach/about_freethought_books/