Odd Squares

Something we discovered today while playing blocks with a 3, 4 and a 6 year old. I’m sure we didn’t discover this. But we didn’t know it. And I haven’t seen this on Crewton Ramone. But, we’ve played a lot with odd and even numbers.

My kids could tell you if a number was odd or even by age two. And now we play a lot with square numbers. So, with the blocks you see things.  Anyway, did you know that if you add up the first n odd numbers you end up with n(squared).

So if you add 1+3 you get 2(squared) or 4. If you add up 1+3+5 (3 terms) you get 3(squared) or 9. It is easy to see why with the blocks.

It was a 4 year old who figured that out. He just figured out the first two, I took it further to see if it works for all. And sliding the squares to the corner it becomes visually obvious why this is so.

Yeah, you should see the proud look on a 4 year old’s face when he figures out that one… just try and get that from a worksheet will ya…