Long ago castles were protected by drawbridges and moats.

People in the castles were worried about attacks from other armies who used bows and arrows or giant catapults to damage the castle and kill the people inside.

Today we designed and made catapults that fired ping pong balls.  We used LEGO men as people on the castles and we tried to attack each others castles using only the catapults.

We are very pleased with our engineering attempts.