This project is about celebrating the pi day with playful activities and, at the same time, working in a collaborative way with several colleagues in-school and out-of-school . March 14th is the International Day of Mathematics.In the wake of this event, our project aims at increasing pupils' awareness of the importance of Maths and making it more interesting to students. The idea is to set numerous interesting and funny activities where pupils have to play with maths:younger children (up to 11 years old) will do geometry activities (mandala, etc), while older children (from 11 to 13 years old) will focus on the circle, the circumference and pi. Students will prepare, exchange and disseminate logic games as well. All the activities carried out during the pi week will be documented in our twinspace, day by day.The project will end with a party, to celebrate the pi day.