This is an inquiry-based activity in which students will need to work together as a class to solve the following problem: they must construct a "boat" entirely out of modeling clay that is capable of supporting 150 grams of cargo without sinking. This activity is primarily intended to be carried out at the completion of a unit on buoyancy in order to assess students' knowledge on key concepts in the unit. Students will work entirely on their own without any teacher assistance to solve the problem in a typical 40-50 minute class period.