Check out this video tutorial to see how to construct an alarm system, that's based on the principle of motion detectors, which work by touch. It's very useful to catch unpleasant visitors red-handed. So make sure your chocolate bar never gets snagged again, catch the bandits with a motion detector alarm! Or just keep you kids away from the birthday present closet where peeping is not allowed.
Get some sticky tape, a battery, a mini buzzer, twenty paper clips, aluminum foil, and electric cable, and two straws. This is what you will make your security device with, believe it or not.