People using crutches have their hands occupied, which makes it difficult to carry books and other items they want to have handy. Student teams are challenged to design assistive devices that modify crutches to help people carry things such as books and school supplies. Given a list of constraints, including a device weight limit and minimum load capacity, groups brainstorm ideas and then make detailed plans for their best solutions. They create prototypes and then test for functionality by loading them and using them, making improvements with each iteration. At a concluding design expo, teams present their concepts and demonstrate their final prototype devices.

Student teams build model hand dynamometers used to measure grip strengths of people recovering from sports injuries. They use their models to measure how much force their classmates muscles are capable of producing, and analyze the data to determine factors that influence a person's grip strength. They use this information to produce a recommendation of a hand dynamometer design for a medical office specializing in physical therapy. They also consider the many other ways grip strength data is used by engineers to design everyday products.

Students explore the physical and psychological effect of stress and tension on human beings. Concepts of stress and stress management are introduced. Students discover how perception serves to fuel a huge industry dedicated to minimizing risk and relieving stress. Students complete a writing activity focused on developing critical thinking skills. Note: The literacy activities for the Mechanics unit are based on physical themes that have broad application to our experience in the world concepts of rhythm, balance, spin, gravity, levity, inertia, momentum, friction, stress and tension.