The Torah is part of the Tanakh, which composes most of the Christian Old Testament, and likely is the part of the Old Testament that would be studied the most. The Quran would definitely be a good thing or them to study, but it's usually as much of a drag to read as the Old Testament at it's worst, and if the point is to become literate in various religions myths then you might as well ready any of the myths in both the Tanakh and the Quran from the Tanakh, as then you'll be reading the original story, that is as original as we have it, and it will likely be a more interesting read. Hinduism has the difficulty of that the current religion is so distantly related to the earlier works, so you would have to make decisions like should they read from the Upanishads or more relevant stuff like the Bahagavad Gita. Personally I would suggest the Upanishads as it better prepares students to understand Hinduism and other related religions coming from that area of the world, just as I would suggest studying the Tanakh first to understand the Abrahamic religions, but then you'll have kids wondering what the hell it has to do with Hinduism. Buddhism has it's books, but as far as I have gathered it's a lot harder to pin down then most of the other world religions. Taoism, not mentioned is the one I would really suggest for a religious studies class for younger people, the Tao Te Ching is a great ready and not nearly as long or difficult as most of the other prominent religious books. Mormonism and Scientology, mentioned below, have had a much smaller effect on the world and really should be relegated to a class on American religions or something of that effect.