There are all sorts of learning objectives you can teach with this one from early primary through to late secondary:
- Light & shadow, color and vision
- Electric circuits - basic series circuits, circuit symbols and diagrams, switches, LEDs and batteries
- Microbes and diseases - transmission of diseases, hand washing and infection, bacteria
- Atomic theory, the atomic model and electron shells, fluorescence and phosphorescence
Step 1: What you'll need
- A couple of blank PVC ID cards
- A 3mm ultraviolet LED
- Some 5mm (or 1/4") thick foam of some sort that squishes and returns to shape again
- 1 x CR2032 lithium battery
I've put together a few links below of suggested suppliers and parts - with postage costs and minimum quantities you're probably looking at $2-$3 each if you order them in 100+. As I order thousands for the workshops I'm running, a couple of people have asked me if I can supply the bits, which I'm more than happy to with everything you need, including the foam already laser cut, white or UV LEDs, pre-printed cards, and batteries (works out around $1.50 each for 10+)
UPDATE: Due to the interest I have setup a little web store to sell these kits cheaply: www.flashlightcards.com
If you'd rather buy all the bits yourself, this is what you'll need:
- ID Cards: http://www.smartcardsupply.com/Content/Cards/cards.htm - the cheapest blank ones here work out at about 15c each in packs of 100 and you'll need two for each card. These are pretty standard world-wide.
- CR2032 Batteries: http://search.digikey.com/us/en/products/CR2032/P189-ND/31939 - these ones are 28c each
- 3mm UV LEDs: http://search.digikey.com/us/en/products/UV5TZ-395-30/492-1321-ND/2407229 - about $1 each if you get 25 or more. Something from 390nm to 405nm works OK but the lower the wavelength the better.
- Foam: http://mdbuyinggroup.com/products/podiatrist-wholesale/plastazote%C2%AE-14-medium - about $11 which would be enough to make 100. I used 5mm, but 1/4" works as well. There may well be cheaper foams - type is not crucial as long as it is about this thickness - just needs to be able to be squished and return to its original shape.