Great Educational on-line Quiz Website - Take a Quiz

I was listening to WSM-AM 650 radio out of Nashville this morning (on-line) as I usually do, and a teacher recommended an educational website: www.sporcle.com. It's loaded with educational quizzes about MANY THINGS. I took the U.S. Presidents Quiz and got 30 out of 44 in 4 minutes. See how you do: http://www.sporcle.com/games/presidents.php
Other educational games include:
U.S. States; Countries of Europe; Countries of the World; Countries of Africa; Countries of Asia; Periodic Table; 3 Letter Body Parts; Commonest English Words
U.S. Capitals; Countries of North America; Countries of South America; Corporate Logos; The Nine Planets