I thought that was what you meant. My ds and I were playing with them yesterday and I discover that but I didn't mention it to him. We did use them Legos to do a bit of adding and subtracting. For example, he made a column using 4x2 but then couldn't find anymore so he used 3x2 and then I asked him how many more he needed, etc. He seemed to like that so I'll have to remember it when it seems time to do multiplication. I just wanted to make sure you didn't mean something different. Thanks.