There are many heroes of Greek myth, and you could do a project focusing on just one hero (choosing your favorite incidents from that hero's life story), or you could do a project where you combine multiple heroes.
Research Tip: Wikipedia is the best place to get started in researching the main Greek heroes: Achilles, Perseus, Jason, and Theseus.
There are also some useful books: The Golden Fleece and the Heroes Who Lived Before Achilles by Padraic Colum, Herakles, the Hero of Thebes, and Other Heroes of the Myth by Mary Burt and Zenaide Ragozin, and The Greek Heroes by B. G. Niebuhr.
Some useful books:
Some Past Projects: