Build A Floating Cork Boat Invent your own cork boats and have a race down a stream. Which boats are the most successful? To build your floating cork boat you will need: Corks Toothpicks Elastic Bands Coloured Paper 1. Insert toothpicks into corks to hold them in place 2. You can also attach corks using elastic bands. 3. To make a sail, insert a toothpick through a triangle of coloured paper. 4. Stick the sail into the cork to finish your boat!