My son is addicted to Numberblocks and we have no regrets in that as he now knows addition, multiplication. Squares, square root,even and odd numbers . What surprises me is that he was able to give reasons behind all these math, that all twos are even and all twos plus one is odd. He can add two four digits numbers in an ease. He is even framing his own linear single digit addition as much as he could. For all that he is only 4 years now. He confidently says that he learned all these only with Numberblocks. He didn’t stop there, he continues to talk in Googlion and candellion also omega, exponentials. I would recommend Numberblocks to all kids out there. The concept to teaching math with 9 friends is simply amazing.