Glow in the Dark Jell-O


  • Jell-O
  • Tonic water
  • A clear glass bowl or clear cups
  • A black light


  1. Microwave 1 cup of tonic water for 45 seconds or until boiling.
  2. Stir the boiling tonic water into the Jell-O mix until it is completely dissolved.
  3. Stir in 1 cup of cold tonic water
  4. Refrigerate your Jell-O for four hours or until firm
  5. Place your Jell-O in a dark room and shine your black light on it.


You can think of light as a wave and as it propagates, it also vibrates. Light from a light bulb, flashlight, or even the sun vibrates in all directions as it propagates. A polarizer only allows light that is vibrating in a certain direction pass through.
Light that reflects off of a horizontal surface vibrates in the horizontal direction (polarized horizontally). So if the polarizer is oriented vertically, it will block that reflection. This is how polarized sunglasses block glare. Now take a look around and see if you can other sources of polarized light.