Make the Box
1. Choose a candy box and carefully take it apart as shown. Make sure it is large enough for your circuit to fit inside. The box I chose is about 6" x 4.25".
2. Paint the outside of the box a color of your choice.
3. Cut a 3" x 2" rectangle on the right hand side of the box front, as shown. This window will allow the input bits to sense light and sound, and allow you to see the light signals.
4. Cut a smaller rectangle (just over 1.5" x 0.5") on the left hand side of the box's "spine". This will allow the battery and cable to come out of the box, making more room for the bits inside.
5. Draw two symbols to indicate light and sound. I used a music note for sound and a light bulb for light, but you can use any symbols you want. You can also decorate the box if you want to.
6. Carefully glue and tape the box corners together, so that the box opens as shown.
7. Apply Velcro dots to the box opening.
Make the Straps
1. Apply the rough side of the Velcro fasteners to the back of the box, as shown.
2. Stick the soft side of the Velcro fasteners to a piece of felt, and cut around them.
3. Put the rough and soft strips together.
Make and Install the Circuit
1. Build this circuit: Power + Split. On one end of the Split, attach Sound Trigger + LED. On the other end, attach Light Sensor + Bargraph.
2. Tape the circuit into the box so that the inputs and outputs can be seen through the window, and the cable comes through the opening on the spine. Tape the battery to the spine.
You've made a Sense-o-Scope! Try it in various levels of light and sound to see how much the sensitivity will need to be adjusted.