I was in Tommy's kindergarten class as usual yesterday morning, and overheard this circle-time conversation...
Ms. F: Is 7 an odd or an even number.
Most of the class: Even! Odd! Even! Odd!
Tommy and a few other kids: Odd!
Ms. F: Odd! That's right. Now...
Tommy: (interrupting) It's also a PRIME number.
Ms. F: (always quick to follow up on a new learning opportunity) You're right Tommy. Can you explain what you mean by that?
Tommy: Well, you can only get to a prime number counting by ones or by itself. Three is a prime number. And so is 7 and 11.
Ms. F: Where did you learn that?
Tommy: My Dad explained it to me yesterday.
Another kid in his class: So prime numbers are odd numbers?
Tommy: Well, I think they have to be odd because if you count by 2s then it's not a prime number, but there are lots of odd numbers that aren't prime numbers. It's different. There aren't very many of them. If you can get to it counting by 3s or 4s or 5s, then it's not a prime number.
They went on talking about it for a little while. They discovered that 12 isn't a prime number because you can get to it counting by 3s. Now, I'm sure most of the kids didn't really understand, but that's OK! I'm just surprised Tommy understood what David was talking about enough to explain it to the class. David just explained it as an aside while they were driving home from swimming on Wednesday.
Yes, my kid is bright, but I actually think this is a prime example of how great schools can be these days. (See what I did there? Prime? Hahaha. I crack myself up.) There's NO WAY we would have talked about prime numbers in my kindergarten class in 1979/1980. Even if I'd picked up the concept somewhere and mentioned it at school -- which I wouldn't have because there was a huge culture of not being a smarty-pants girl back then -- I know my K-2nd grade teachers would have shut me down. There's no way they would have run with it like Ms. F. did. They would have told me not to talk about it because it's "too hard" or not in the lesson plan for the day.
We've come a long way, baby.