Prepare gelatin the night before to allow it to set up.
- Put wax paper into the gelatin pan so you can remove the gelatin out of the pan in one piece.
- Cut the gelatin with a sharp knife so you can shine lasers into a smooth flat surface. Do not use a serrated knife to cut the gelatin, the surfaces must be as smooth as possible to minimize reflections at the surface.
- Shine a laser into the gelatin at an angle (like the sun picture).
- Move the laser (or gelatin) around to see different refraction angles.
- Shine parallel lasers through a diverging lens into the gelatin to see the divergence.
- Shine parallel lasers through a converging lens into the gelatin to see the convergence to a focal point.
- If you don’t have any lenses, cut lens shapes out of the gelatin for this part. It still works pretty well.
- Follow the figures and place a converging lens so that the laser focus on a “retina.” Move the lens closer and further from the “retina” to simulate farsightedness and nearsightedness.
- Correct the vision with the appropriate lens.
- Cut odd shapes out of the gelatin and let the kids shine lasers into them. Be creative!