This is an engineering activity that requires students to build a mousetrap car based on certain constraints. Constraints include students having a virtual budget that they use to buy approved parts for their car, the car having specified maximum dimensions, and a minimum required distance of 3 meters that the car must travel. The activity does a great job of requiring students to consider trade-offs, design a solution, test their design, make changes in their design, and then make a final decision about their solution based on data and performance.