As part of the forces and motion unit my students had the opportunity to play around with the RAFT Retractor Car Activity Kit . The modified activity [available at https://docs.google.com/document/d/17grd41wMyBj7kjTaZgBZk7x-trCcrDeQxNyx1LWYRhc/pub] involved the students building the vehicle [as specified by the project page] then deciding what they wanted to test. Students had several options: how will the car perform over various surface types? how might the speed or distance be impacted if the car has to travel up an incline? how would increasing the mass on the car impact the speed or distance the car travels? how could the design be adjusted to make the car go further or faster? As usual, only one person selected to try this activity, at least until the rest of the students saw the car cruise across the classroom floor. Thank goodness for those students who are ‘early adopters’ and willing to try something unknown. In the end there were several groups who performed the surf...