http://www.colorvisiontesting.com/
"Are you colorblind? Have you ever wondered why colorblindness occurs? Do you think you are colorblind, but aren’t sure? Well, this site has answers and explanations that will answer all these questions.
What is Colorblindness? – This section covers what colorblindness is and describes the different types. There are four different kinds and they are explained in detail with a color chart for each.
Why Are You Colorblind? – This section discusses the science behind it. Why exactly are people colorblind? It also goes into detail here why more men are colorblind than women. It was a pretty fascinating read.
The next four sections all deal with helping you diagnose children with colorblindness and if they are colorblind, how you can tell, what you should do and how to effectively teach them.
Do you want to test your vision? Well, you can test for colorblindness here at the site with the “I Want to Test my Color Vision” section. You go through several different flashcard type exercises where you should see something if you aren’t colorblind. Don’t worry, they walk you through it! It’s pretty easy.
My favorite section is the one about how the world looks to people who are colorblind. I mean, I’ve always wondered. So, you get to see some of the test examples and such, but under those, there is a link to see how the colorblind see certain color palettes. Click that link and then choose one of the types of colorblindness and watch the palettes change. This gave me a much clearer understanding of how the colorblind see things.
I learned so much from this site. I hope you do too! "