This is interesting. I found it way too hard to interact with the ball and ended up reaching level 14 by doing basically nothing. I was also a little confused about the math equations, for example, when the game displays "-2 =/= 0", that is already a correct statement, but the way to progress seems to be to change the -2 to a 0.
I came to understand that what the game was saying was that the left side did not match the right, and it needed to be altered in order to match. This might have been clearer if it just said "-2 = 0" and had a red X or highlight to indicate that it was incorrect, which could then change to indicate a correct value when appropriate.