Playing with Rods

We've seen some more free play with the rods again. It's amazing to me how much fun both of the boys have with just playing around with these things. Yesterday, Hero built a semi-symmetrical tower. Today, I explained that a square has to be the same length on all sides or it's really a rectangle. Then, I asked if he could build a square out of only black rods. The tower with all the squares in the base was the result.