This is the single best (and I rarely use absolutes) resource I have found for teaching Shakespeare -- I recommend you take the time to become familiar with all of the included resources. You will transform your class if you do.
Shakespeare in Action - Virtual Lab
And, if you have time -- (and I hope you find the time) - check this out as well.
Shakespeare, Subject to Change (A Cable in the Classroom reosurce.)
Lastly (not really) - Do an "app" search for Shakespeare in iTunes, or on your iTouch or iPad. Some of the apps offer a free preview that, in their brevity, have some useable features. You are free of course to purchase them ..