For a great project on Hinduism, and to learn the important vocabulary of this religion, write words related to Hinduism on pieces of paper and put them in a hat. Two kids draw a word, and then have to act it out or tell a story that illustrates that word without actually using the word, while their teammates try to guess the word. Some good words to use include:
Another good project would be to write stories, poems, or plays, or draw pictures or comics illustrating reincarnation or dharma or karma. The kids could look through newspapers for articles that seem to them to illustrate dharma or karma, too.
Bibliography and further reading about Hinduism: