Each group has 20 minutes to build a bridge to span across a bowl of water.
Any other suitable building materials
The idea of this game is simple - split your group into teams of 3 or 4, and give each team a "Building Kit" (explained below) and a bowl of water. Each group has 30 minutes to build a bridge to span across a bowl of water.
At the end of 20 minutes, each group has to demonstrate their bridge. You then test it for strength by adding pebbles one at a time, until the bridge collapses. The team with the strongest bridge wins!