Under development
Refraction: the bending of light when a light beam passes at an angle to a surface between two optically transparent materials of differing densities.
Monday demonstration included a laser, prisms, and half-round dishes with water to show bending of light.
Wednesday moves on to introduce convex and concave lenses. Use magnifying lens to produce an image. Introduce object distance and image distance. If sunny, use the pinhole and paper punch hole camera to demonstrate pin hole cameras and effect of aperture size on clarity. Move on to explain human eye, iris and pupil. Move on to cover myopia, hyperopia, presbyopia, and remedies.
Another demonstration that fits here is the coin under the glass of water.