If you need material on science or atheism vs. Christianity, check out this math professor from Oxford (England). A very kind person, but tough, straightforward material (with a bit of whimsy). He’s put himself in very challenging situations, including coming up against the beliefs of Richard Dawkins (“the world’s most prominent atheist”), Stephen Hawking, and other famous unbelievers. At Lennox’s website you can find a number of resources, including videos of some lectures. One video lecture titled “Is Belief in the Supernatural Irrational?” took place on the campus of Harvard—and received a standing ovation. I could picture small groups watching this lecture and pausing occasionally to discuss.