MATERIALS/ SOURCES (NL) • Activities An Analogy A (NL) An Analogy B (NL) One Bulb, One Battery, One Wire (NL) The Bulb Challenge (NL) Look at all those bulbs! (NL) Light that bulb! The Closed Circuit Challenge Look at all those batteries! (NL) Enter: the switch! (NL) Look at all those switches! (NL) The Switch Challenge (NL) Turn on the buzzer! (NL) Connect the motor! (NL) Adding a photocell and LEDs (NL) My own car door (NL)