British Museum: Ancient Athenian Theater
http://www.ancientgreece.co.uk/festivals/explore/exp_set.htm
Students can explore a mock-up of an Ancient Athenian Theater by clicking on various items, people, and locations.
Gallery of the Gods
http://www.mythologyteacher.com/Gallery-of-the-Gods.php
This site provides a good overview of the major Greek gods and goddesses mentioned throughout the play.