This video covers what wavelength and frequency are, and also how to calculate them from the equation: speed of light = (wavelength) x (frequency).
The Electromagnetic Spectrum
Most physics and chemistry teachers will expect you to know off the top of your head whether red or purple light has a longer wavelength, what the "visible spectrum" is, and how X-rays and UV-rays stack up. This video covers the whole E&M Spectrum, and gets you up to speed with what very well might be a question on your next test.
Photon Energy & Planck's Constant
By the end of this video, my hope for you is that every time you see the words "photon" and "energy" in the same sentence -- even if you're in the grocery store -- you'll immediately think of the equation E=hf.
A strange little unit of energy that's only used when physicists are talking about photons and particles, this video explains what they are and how to convert to them from Joules. Btw, hilarious science jokes in this video.
If you do not have an account, you should get one, because it is awesome! You can save a playlist for each test or each chapter, and save your "greatest hits" into a "watch right before the final" list (not that we recommend cramming, but when in Rome...)