If you’ve been involved in a Christian small group for any period of time, invariably someone requests that you do a lesson series on world religions. My Sunday School class has done several studies, most recently using Barbara Brown Taylor’s Holy Envy.
Taylor has a thought-provoking approach to other faiths, with individual chapters devoted to Islam, Hinduism, Buddhism, and Judaism. The balance of the book introduces ways in which Christians can grow by having a better understanding of our brethren from other religions (and other Christian expressions of faith for that matter).
Reply in the comments if you have reflections on this series!