Given the velocities of two toy buggies, predict where to place them along perpendicular meter sticks so that they collide (video). Extra: show that you get the same prediction using both graphical and equation-based approaches.
Similar as above, but replace one of the buggies with a cart/marble/etc going down an incline. You can also use a fan cart.
Release a cart on an air track pulled by a hanging mass such that it crosses a finish line at the same time as a constant velocity cart. Video of set up.
Level 1: Stagger Cars so they hit the wall at the same time.
Level 2: Given a random distance, determine where the two cars will collide.
Level 3: Given a random starting position and line placement, determine where the cars will collide with perpendicular paths.