Since the beginning, Alex’s favorite Cuisenaire rod game has been one where we put two “rod stairs” together so that you get a rectangle made out of addends of ten. (10+0, 9+1, 8+2, etc.) Then one of us closes our eyes while the other one removes one or more rods, and the person whose eyes were closed has to guess what was taken by looking at what is left. It’s a pretty easy game, but the sneaking around is fun for her.
The last time we had the rods out, I decided to mix it up.
I made a random combination of rods that equalled 20: 5+3+2+8+1+1. Then I matched it up with some other patterns that make 20: 10+10, ten 2 rods, and 3+3+4+4+3+3. She thought this was neat all by itself. We played the remove-and-guess game a while with this new configuration of rods. This adds a memory component to the math component, because if you remove, say, the five rod, it could be replaced by a number of other combinations of rods.
We played for a while. Then I told her that I was going to try something new again. I took out two rods (3 and 4) and replaced them with another (7) that was equal in length. She had to find the interloper and replace it with the original two.
You kind of can’t go wrong with this game, because whether or not you guess the right rods you’re strengthening your understanding of number relationships. I love that about rods.
When it was Alex’s turn, she took out an orange rod and replaced it with another orange rod. She was very pleased with herself for tricking me. I told her she couldn’t do that because I had no way of telling them a;part, but in retrospect I realize that for a four-year-old, the fact that 10=10 and all 10s are interchangable may in fact be a nonobvious concept and one worth exploring. I have got to stop letting my preconceptions get in her way.