How to Build a Magic Knocking Box

Place a sheet of newspaper on a table. Place an empty keepsake jewelry box with the lid open on the newspaper. Pull out and dispose of any velvet or other padding at the bottom of the box.

Cut a slit with a utility knife. Go through the box, from the bottom left corner and up two inches. Smooth the cut with fine-grit sandpaper. Wipe the cut with a dry paper towel.

Place the jewelry box on the newspaper. Tape wax paper around the outside of the box with strips of masking tape.

Spray the inside of the box with the matte black paint. Let the paint dry for 3 hours and then reapply a second coat. Remove the wax paper from the box and dispose of it once the paint has dried.

Place a coin inside the box and close the lid. Rotate the box in your hands while knocking on each side to show that there is no hidden opening. Palm the coin when it falls through the cut. Open the box to show that the coin is gone.

Close the lid and repeat the procedure of rotating the box and knocking on it, only this time pushing the palmed coin through the slit, so it goes back inside the box. Open the lid to show that the coin has returned.