I am from Serbia, and I am a part of a team of game developers. Sorry for English, but I don't speak Czech.
We have some very good game for kids and know I would like to present you one very good game - it is a Math game for 2 players. It is called Math Fight - Fun 2 Player Mathematics Duel Game for Free
I hope you will like it, it's free!
+ Split screen interface makes this brain game a 2-player reactor
– Basic math workout means this is mathematics for kids 7 years and above
x Math speed training improves math skills, reflexes and concentration
÷ Educational game for teens that is at the same time a fun game for free
https://itunes.apple.com/us/app/math-fi ... 47827?mt=8