Lanyard-mountable LED throwies

At the last “HacKidThon”, we showed a passel of kids how to make LED “throwies”. Each one is a nothing more than an LED, a coin cell battery, and a magnet so the contraption can stick to metal surfaces, walls and buildings, and hang there glowing.

This week, someone asked me if we could modify the classic design somehow so that the LEDs could be attached to lanyards, instead of magnets. We wanted it to be as cheap and easy as the rest of the “throwie” recipe.

A little brainstorming with Eleanor, and we came up with this: plastic-coated paperclips!

The paperclips actually help hold the LED leads in place; we put tape around them as usual, though that’s not shown in the picture. The plastic coating keeps the paperclip from shorting out the positive and negative battery terminals.

The coated paperclips cost less than a penny apiece, and come in colors that match the LEDs. Victory!