I've heard of them both. I did not try the prism classes. But I did get my son evaluated for vision therapy. The practioner was not able to treat my son although he agreed he needed treatment. The practioner admitted he did not have the necessary experience.

However, I also had my older son with ADHD evaluated and the vision therapist knew exactly what to do with him. We did vision therapy for 18 months. My older son's balance improved, reading and homework completion quicker and more successful, "eye aches" went away, and he quit tripping all the time. I'm so relieved that we found this treatment early in his school years.

My 8 y/o son was in a year long study for prism glasses. It really helped him train his eyes on where to focus. His reading greatly improved. The key for us was to do the eye exercises twice a day, everyday. I did my best to make it into a game.

Tip: We tried when he was younger and didn't have much success. The test the doctor required was far to detailed and the glasses they gave him were held on to his head by a elastic band. He hated them I would have too if it were me. When he wore regular glasses he tolerated them far better than I would have ever guessed.