This inquiry activity should be completed before discussing with students that a projectile’s motion in the vertical direction is independent of its motion in the horizontal direction. As long as students use their apparatus carefully and don’t flip coins in the air or launch them at an angle, they will clearly see that a falling coin and a projected coin will hit the ground at the same time. There are many apparatus available for demonstrating this, but allowing students to do it on their own will result in better understanding and longer retention.