- Topics: Area, Measurement: Book: Sam’s Sneaker Squares by N. Gabriel.
- Topics: Area, Measurement: I printed out a variety of outlines of shapes (download here). The kids had to figure out the area of each shape, using 1.5″ by 1.5″ square tiles (actually, they were a mix of 1.5″ by 1.5″ tiles and 1.5″ by 3″ tiles, from the board game “Caverna”). We also discussed how you could figure out the area without explicitly counting.
- Topic: Logic: I discussed the following problem (courtesy of Kevin Bourrillion): Anne and Bob have each watched Frozen at least once. I know how many times they each have watched, and I tell them that one of them has watched one more time than the other. They then have the following conversation:
- Anne: I don’t know how many times you have seen Frozen.
- Bob: I don’t know how many times you have seen Frozen either.
- Anne: Oh, now I know how many times you have seen Frozen.
- Bob: Oh, then I now know how many times you have seen Frozen as well.
The problem is to figure out how many times Anne has seen Frozen. (Note that Bob does not update his beliefs after hearing Anne’s first statement, otherwise there are two answers).
- Topic: Logic: We did 4 different logic puzzles from Mindware Math Perplexors: Basic Level. Each kid had their own print-out. The first two I read the clues to the kids (I only gave them the bottom half of each logic sheet), the next two they read on their own.
- Topic: Games, Attributes: We played half a game of Set, with two teams of three.
How Did It Go?
All six kids attended.
Several of the kids already knew you could use multiplication to compute area. This series has a nice mix of math and entertainment.
I tried to get them to guess ahead of time the area, they mostly just wanted to start filling up without guessing. It was about a 50/50 split for kids who thought the 4×4 square was bigger/smaller than the 6×2 rectangle. Some of the shapes you could have been clever, e.g. using symmetry, but they almost entirely brute-forced it. A follow up could be to have much bigger shapes where brute force takes too long.
I started by discussing a simpler version, where Anne immediately says “I know how many times you have seen Frozen.” The kids got close but didn’t quite solve this without help. Then I asked a version where Anne doesn’t know but then Bob does. At first they got it wrong, but then one of the kids said you should cross off 1 for Anne (just like you would in a logic puzzle). From here we were able to work out the solution to the full problem.
A few of the kids had trouble with the first couple problems, but most of the kids solved the last two on their own with little help — they can all read the clues on their own now. One of the problems involved turtles with nicknames Speedy, Zippy, and Zoomer, which the kids thought was funny. This activity went much quicker than I expected, so we had time to play…
At first here was a LOT of incorrect, fast, loud guessing, some card touching/grabbing. After a bit I came up with a rule that worked pretty well, which was that 1) they couldn’t touch the cards when naming a set, and 2) if they got it wrong, then that team couldn’t guess again until the other team had a chance (or after a certain amount of time, about 10 seconds). Also, if they were having too much trouble finding sets, then I would name it and get it :). Mostly they had trouble with sets where all the attributes are different, which isn’t surprising. In the end, one team had 4 sets, one had 3, and I had 4.