This site explains how we arrived at the names of the days and months we use today, as well as outlining the history of our calendar. Do you know what a day, or a year, really is? (
http://www.indwes.edu/Faculty/bcupp/things/Greenwich/Calendar.html
)
This “Mensa Workout” is a quiz full of brain teasers. After completing the quiz, which takes about 30 minutes, the site calculates your score, tells you how you did, and reveals the correct answers. (
http://www.mensa.org/workout.html
)