PERFORMANCE TASK
Pete owns a pet shop. He sells many kinds of fish. The fish need clean tanks to stay healthy. Pete doesnʻt like cleaning fish tanks. It bothers Pete to put his hands in the water. But it takes a long time to take the fish and the water out of the tank. Pete has hired you, as an engineer, to apply your understanding of the properties of magnets and magnetic fields to plan ways to solve the problem, make and test a prototype tool that can be used to clean a fish tank, and revise your design to make it even better. Pete says that your tool must meet this criteria for success: Your cleaning tool must clean one side of the tank in 30 seconds. Your solution must also stay within this constraint: You may use no more than 4 magnets.
ANNOTATION
This example is proficient on the trait of design because the student provides a photo of the aquarium tool cleaner and labels the four disc magnets and scrubber that will be used to clean the aquarium in 30 seconds. The student provides a reason as to why the four disc magnets would be stronger to clean the algae off the tank than the bar magnets: “When we tested the magnetic force the disc magnet could pick up twice as many paper clips as the bar magnet.” The student also explains why she would use the sponge rather than the sandpaper: “The sandpaper is too scratchy and might not take off all the algae and the sponge is softer and can turn corners.”
This sample shows proficiency at the testing level because the student tests her design and then explains refinements that relate to the design problem: “The scrubber was flexible and had a good magnetic force and could take off the algae in 30 seconds.” “The glue dots werenʻt very strong and fell off.” “I would spread out the glue dots so they cover more space and connect to the magnets in more places.”
