Children aged 8 to 12 (tweens) of the new generation have to get away from their computers/game consoles and start moving again. That was the input and challenge for the innovative sports concept for children project. The solution was the spray skate. A new concept based on an already existing sport. This inline skate could be used to draw on the streets while skating: leaving a trace. According to the movement of the skater the skate would leave a trail of special chalk spray. This spray could easily be removed with water (rain). For instance when jumping, performing tricks, and even combo's. In this way they could draw on the streets by performing and improving their movements. The combination of a microcontroller and a multi-axis accelerometer made it possible to trace the movements and define the output of the actuator controlled chalk spray. By implementing the skate in this way a physical game was created with game elements of (online) games: fun, competition, skill development, challenge etc. In this team project I was strongly involved in the User Research, concept generation and made a fully functional prototype.