Whoever has said that one cannot learn by playing is totally wrong. Nowadays, there are a number of games which offer some kind of teaching to reinforce the knowledge both adults and children have.
A clear example of this is Tests-Mania, an excellent game which consists in numerous tests, which have around ten questions related to varied subjects.
The user will have to answer each question, having three options to choose from, only one of them being correct.
This way, whoever dares to measure their knowledge will have to answer on different sciences and will have the possibility to carry out 200 tests approximately.
In short, with Tests-Mania, you will manage to measure your knowledge and you will be able to learn from your own mistakes whenever you make a mistake at the time of providing any answer.