School house rock is one of those shows that I watched as a kid that made certain things really interesting to me. In a middle school social studies class I feel like these lyrics along with the videos which can be found online can be a great introduction to a unit.
This site is a good resource for teachers to find helpful information about any particular subject. This site is where my Crotched Mt. teacher found IXL to use for she students.
Testimonials on a variety of topics from experts. They for the most part are extremely thought provoking. It covers opinions of topics ranging from "Just War Theory" to Cognitive innovations.
This site is a great tool for anybody looking for activities to help teach particular topics. It's divided up by grade, then by subject. I find this particularly useful for those who are extremely interactive.