European challenge on mental calculations

The competition is free and open to all (school or not, teenagers, adults). It takes place from June 18, 9am to June 25, 8pm, Paris time. You can play as many games as you want.
The website and the game are available in six languages (English, French, Spanish, German, Italian and Dutch).

Statistics on various aspects, including the number of games and the score evolution of a player will be calculated and published on the website and at the ICME13 conference.

This game stimulates mental calculation and is a simple example of what is possible with the TQuiz editor for a fun presentation of mathematical concepts. More examples are available on

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