Make a circuit board using a sheet of stiff card.

Cut out strips of kitchen foil like those shown on the diagram on the main screen.

Stick them to the card using glue. Notice that we didn't stick the ends down!

Now place the battery and bulb on the board (double-sided sellotape can keep them in place) and make sure that the foil strips touch the connections. Tape them in place or they may come loose and stop the circuit working.

Turn the battery around and see if it makes any difference. Then do the same with the bulb.

Note: when things don't work it is usually because you did not connect all the metal parts together firmly!