Floating Our Boats Will they Float? We made boats for homework as one of our tasks on transport and we filled a big tub with water to see if they would float. All the homemde one floated and only two lego ones sank. We thought that was because they were too narrow at the bottom because one lego boat floated. Gabe's boat was made out of cardboard in the shape of a bread bag clip and a cylinder. When 12 drops of detergent were put in the cylinder the boat moved quickly across the water. We are still trying to find out why?   Classwebsite1_2 Menu