I went to Landmark College in the mid-90s. It was at the time the only accredited institution in the United States that specifically taught students with learning disabilities (primarily dyslexia and ADD, which I have both.) When I entered in the fall of 1995, it was $32,000 a year. I have no idea what it is now, but I shudder to think.
The main reason Landmark was so expensive is the salaries of the faculty, and they're not paid particularly well. When I was there, the student:teacher ratio was 2.5:1.