Materials:

Dry cell and battery holder
22 gauge insulated hook-up wire (Radio Shack)
Nail
Miniature 1.5 volt bulb (Radio Shack)
Miniature socket to fit bulb (Radio Shack)
Cardboard

• Use the nail to punch six holes down the left side of a piece of cardboard and six holes down the right side.
  
• Cut the wire into 6 pieces that will comfortably extend between any hole on the left side to any hole on the right side of the cardboard.
  
• Strip 1/2" of the insulation from both ends of the wires. Place the end of each wire in any vacant hole on the left and the other end in any vacant hole on the right. Secure wires in place with hot glue.
  
• Cut another length of wire, strip tile ends, and connect one end to one of the dry cell holder
  terminals and the other end to one of the socket terminals.
  
• Connect a second wire (with the insulation stripped off the ends) to the remaining terminal of the dry cell holder.
  
• Attach a third wire (with stripped ends) to the remaining terminal of the socket.
  
• Test: by touching the two free ends of tile wires together briefly, the light should go on.
  
• Write a question next to one of the holes on tile left side of the cardboard. Follow the wire from the left side to its end on tile right. Write the answer to this question next to the hole on the right side of the cardboard that holds the opposite end of the wire. Continue this procedure for all 6 wires.
  
• Ask a friend to take the two free ends of the wires from the cell holder and socket and touch the matching questions and answers. Tile light bulb will light up when the answer is correct.
  This works because the circuit is completed by touching the question with one end of the wire and the answer with the other.