Set up a tennis ball launcher. Ask students to calculate the distance that a tennis ball will travel absent air resistance. Next, have them do a lab experiment in which they measure the actual distance traveled. Have them explain why the lab results differ from their calculations. For students who have learned how to account for air resistance in their calculations, ask them to adjust the launch angle of the cannon in order to have the projectile hit the landing spot that it would have hit on the first launch without air resistance.
Doing physics problems is often more enjoyable in the context of a game. In addition, students can learn from their peers when doing team activities. Split students into two teams and have them adjust the launch angle of the cannon to have the projectile hit various targets on the floor. For more advanced students, put some of the targets above ground level (such as on a chair).
A coin toss is an example of projectile motion, with the coin being the projectile. Have students predict whether and how the mass of a vertically tossed coin will affect how long it takes for the coin to return to the location from which it was launched, neglecting air resistance. To ensure a consistent initial velocity, have each pair of students toss a penny, a nickel, a dime and a quarter vertically. Glue an index card to a spring, compress the spring, place the coin on the card and release the spring. Have students record the flight time of each coin. Ask them to explain the results and any discrepancies between the results and their predictions.
After students are able to calculate how far a projectile travels horizontally, they should learn to calculate how far the projectile travels vertically. Set up a dartboard and a toy gun with suction cup arrows. Tell the students that the gun must be perfectly level and must be exactly 10 feet from the dartboard when shooting at the board. Students must calculate the correct height from which to shoot the dart so that it will hit the bull's-eye. Score the game as you would a game of darts.