In the second stage minigames happen. It is a time limit, but which is not clear - a clock is ticking, but when it has expired? That puts the children badly under pressure so that they no longer really expected, but like a rabbit sitting in front of the snake there. In addition, the calculation time is quite short. Overcome a first year "7 + 6" or "double 12" not fast (enough). Take out the time limit; the players yell at some point.
Some tasks are simply read out too fast.
The software may be an update tolerated. A thorough. Then the game could probably be fun.