You will need:

• A long cardboard box or tube. Any shipping box will do. If you don’t have a long box, you can tape two together to make one long box. The length of the box will determine the image size – the longer the box, the larger the image.
• Scissors.
• Duct tape.
• Aluminium foil.
• A pin or a thumbtack.
• A sharp knife or cutter.
• Sheet of white paper.

What to do:

1. Cut a rectangular hole on one end of the box using the sharp knife.
2. Using the scissors, cut an equally-sized rectangular piece of the aluminium foil. Make sure it is not crinkled.
3. Tape the foil over the rectangular hole you just made in the box.
4. Use the pin to poke a hole in the center of the foil.
5. Place or tape the sheet of paper at the other end of the box.
6. Stand with your back towards the Sun. Place the box on your head with the hole towards the Sun. Adjust your position without looking at the Sun directly or through the pinhole until you see the Sun’s image on the paper.

http://www.timeanddate.com/eclipse/make-pinhole-projector.html