Students hammer nails around the edge of the board, with a curve at the top. Stretch elastic bands over to make a wall around the board.
Make the marble launcher: slide the spring onto the nail then insert the nail through the drywall anchor. Attach the launcher to the bottom corner of the board, inside the wall (right or left side, depending on the handedness of the student), using a staple. Add a blob of hot glue (or an elastic band wrapped tightly) to the end of the nail that is pulled, to stop it from leaving the shooter when it is released.
Make a channel for the marble to travel up after it is released.
Add more nails and elastic bands to the board as desired to make obstacles for the marble.
Add scoring boxes at the bottom of the board.
Nails I used:7/8" X 17 Ga. 2oz enough for 4 students.