hey, i know a way you can impress you physics teacher. If you have a copy of Dark Side of the Moon.....take in the album cover. And talk about the "Visible Light Spectrum" This is the amount of light the human eye sees. In its proper order the visible light spectrum in red orange yellow green blue indigo and violet.
if you were to pass a single beam of light through a prism, you would be able to see this.
And hey.....that's the Dark Side of the Moon cover
See....Pink Floyd can solve all your problems :p