The jatakas are "birth stories" told by Gautama Buddha as parables for the members of his community. There are hundreds of them, and they are one of the oldest folktale collections in the world. As you work with the jatakas you will want to find a theme or topic to help you choose three or four stories to put in your collection. That might be stories with a similar moral or lesson, or stories about a particular animal, etc.
Research Tip: Start with some background about the jatakas at Wikipedia. Then start exploring; there are some wonderful jataka collections online. Some are retellings for children, like the books by Babbitt, Rouse, and Inayat Khan. There is also a nice collection by Shedlock and Varma. You can find literal translations from the ancient Pali texts in the editions by Rhys Davids, Francis and Thomas, and Cowell. If you like comic books, you will enjoy the jataka comic books on reserve in Bizzell Library.