I just received an email from C-SPAN reminding me of a great free PD opportunity that they offer for teachers in the U.S. during the summer. The Summer Educators' Conference is a free event happens on July 12 and 13 in Washington, D.C. You do have to apply to participate. If accepted, C-SPAN covers all costs of attendance including airfare and lodging. The focus of the conference is on using C-SPAN's vast digital archives to develop lessons for social studies. You can find all of the details including the application, here.