We always had a great time playing Boggle when I was a kid. Our whole extended family would play at the holidays--sometimes so many people were crowded around the table that it was hard to see the letters. We haven't yet broken it out with our kids, but this reminds me that we should!
We play the "Last-Letter Game," which is great for car trips and for long waits in line. The first person picks a word that starts with A, say "alligator." The next person has to pick a word that starts with the last letter of the previous word, so in this case, and "R": "rigamarole." Repeats are not allowed, so silent e's and y's get tough after a while. DS7 loved this game last year!
The game Sorry! is good for young kids with a number obsession, as is Hi-Ho Cherry-O.
Battleship teaches coordinates in a fun way, assuming you don't mind the war aspect of the game. I used to love Risk, and there's some geography, probability, and strategy going on there. Monopoly was one of my favorites, too, and with the money and the strategy, I think that's loosely educational, at least for a young child.
(I'm stretching the limits of the term "educational games, I'm sure. But these are/were the popular games in our household, and I think the "game" part of the term shouldn't be underestimated.)
