I have a friend that is colorblind, meaning they have a decreased ability to see color or differences in color.  Do you know anyone like that?
Yes, my uncle is also! We always play tricks on him like getting him a birthday card only printed in a certain color he can't see.
I understand it can make some educational activities difficult though - for instance teaching a child their colors
Yes, I can't imagine. They have a special kind of glasses now that can correct color blindness.
Color blindness
Color blindness, also known as color vision deficiency, is the decreased ability to see color or differences in color. Simple tasks such as selecting ripe fruit, choosing clothing, and reading traffic lights can be more challenging. Color blindness may also make some educational activities more difficult. However, problems are generally minor, and most people find that they can adapt. People with total color blindness (achromatopsia) may also have decreased visual acuity and be uncomfortable in bright environments.
The most common cause of color
1964], Giuseppi Logan was 'studying' with me, meaning: he wanted to know certain things, and I needed an alto player, so he played all of my concerts, and occasionally I would let him have some of his things played in the group. He had a great deal of difficulty with getting people to play his music. I think at the time I was the only trumpet player who could play his music, and I loved playing it.
No one sounded in an ensemble like Giuseppi.