Old eye glass lenses
Projector lenses
Christmas tree ornament
"Baby moon" hubcap
Soft drink can bottom
Broken optical instruments
Glass flask and water
Clear plastic rods
Narrow olive jar and water
Styrofoam food trays
Rubber cement
Etc.
Procedure:
1. Have students experiment with the optical properties of old lenses and mirrors and other objects that reflect or bend light. (See the discussion below for ideas on obtaining materials.)
2. Make a simple and nearly indestructible magnifier glass out of styrofoam food trays, rubber cement, and old eye glasses. Cut a three piece "sandwich" from the styrofoam tray. The pieces should look like ping pong paddles. Lay a lens in the center of one of the pieces. Cut a hole in the styrofoam exactly the size of the lens. Cut slightly smaller holes in the other two pieces. Glue the three pieces together with rubber cement. Refer to the Build Your Own Telescope activity for more information on the
construction technique using rubber cement.
3. Make a concave mirror by polishing the bottom of an aluminum soft drink can. Obtain polishing compounds from a hardware store. Use the compound and a damp rag to achieve a mirror finish.
4. Make crude telescopes by aligning old camera and projector lenses inside a paper tube.
5. Observe the images produced with a silver glass Christmas ornament or a Baby Moon hubcap (available for a few dollars from an auto supply store)
Discussion:
An amazing collection of lenses and mirrors can be obtained at little or no cost through creative scrounging. Ask an optometrist or eyewear store if they will save damaged