This exercise is designed to help the students combine their own ideas
and pre-existing skills and knowledge from outside the realm of
electronics into the topic at hand, and it prepares the students to the
creative, project-based approach.
The exercise makes use of the behavior of light. The light of an LED is
very directional which means the light must often be reflected,
refracted, dispersed or filtered with different materials in
actual lighting devices. Creating shadows or placing LEDs inside objects
or crafted items will also change how the light looks like.
Ideas for facilitating the exercise
You can extend this exercise into a longer teaching session, instead of
an independent exercise.
Some ideas:
- Give the students an LED and a 3V coin cell battery (with safety
cautions!) and ask them to test different materials and ideas as
their home work. Students present their findings and finish the
exercise in the beginning of the next lesson
- Have a look at the list of possible materials below and provide a
selection of them in the classroom for the students. Some crafting
tools are also useful.
- Instruct the students to go around the school for a certain amount
of time and make perceptions - can they find materials that can be
used for this exercise? Provide the students with an LED and a 3V
coin cell battery (with cautions!)
- Instruct the students to make observations on materials and
techniques used in actual lighting devices around them and as
presented online. When would they use direct LED light? When is it
important to disperse light first
- Giving the students a time limit of eg. 15 minutes may make it
easier to concentrate and get the exercise done effectively. Time
limit will help to keep the project small and simple enough.
Making observations outside the classroom and harvesting the materials
is a good start!
Ideas for materials
If students are struggling, you can give them a hint of some materials
they can try out.
Change the way the light travels:
- Cotton pads
- Plexiglass (scraping, carving or milling the surface of the
plexiglass will change the reflections)
- Ping pong ball
- Straw
- Polymorph (thermal hobby plastic which melts in 60°C)
- Hot glue
- Tin foil
- Colored glass
- Colored plastics
- 3D printed custom shader
- Hair gel (Make sure the LED is insulated from the actual gel with
for example transparent plastic!)
- Thin paper (make holes, an origami, combine with other materials and
items...)
- Popcorn, marshmallows, cotton candy
- Cellophane - colored, clear, crumpled
- Strong shadow: LED behind a non-transparent shape
- Cocktail parasol
- Transparent dice (drill a hole!)
- Packing foam
- CD’s
- Bandy balls
Put the LED into a new context:
- Perler bead art (also known as Hama beads): leave holes into the
artwork for LEDs
- Cardboard structures
- Replace the eyes of a plush toy with LEDs
- Dollhouse lighting
- Origami
Use LEDs from other devices:
- Salvaged LEDs from discarded christmas lights
- LEDs from toys