Many. My eyesight started deteriorating when I was probably about 10 and my first eye exam was at 11. I couldn't see the white board at school anymore at that age so I had to stand next to the projected screen to see and take notes
Yes, I've gotten glasses twice, so they had to test my vision. I also had some test for cataracts are glaucoma or something where they shoot a puff of air into your eye because I suspected I might have had one of those things. I didn't.