Redstar,
I had similar experiences in my schooling. From 2nd-4th grade I was in a day school like that. From mid-6th-8th I was in another day school. From mid-10th through my graduation I was in that type of school residentially. I can remember visiting the first school for the first time carrying a book on hominids I was reading along with me. It turned out that very little science was taught there at all. At the first of two residential schools we would spend first period reading Harry Potter aloud. In my free time, (which was very limited due to the structure of the program) I was reading Kabbalah and Its Symbolism by the scholar Gershom Scholem. While I was there I got picked on a lot by the other students for adhering so much to the rules. A number of staff members were openly suspicious of me because I was so good about following all of the rules and didn't appear to get involved with the types of schemes the other residents tried to pull off. When I finally had a meltdown after 6 months that was very serious one of the staff members triumphantly declared, "I knew it. Finally the real you is showing through." Because the nature of the program was one of confronting very harshly and amplifying the difficulty of situations that were hard for a resident I just seemed to do worse and worse. My last month there was spent on a couch in a corner of the dining room facing a window, except for nighttime when I slept in one of the bedrooms.
I don't know if it is the same for you, but even though I wasn't intellectually satisfied and my own behaviors and predilections weren't typically understood by the people around me, I find the time spent there was worthwhile. I learned to understand the people around me in a much smaller setting than a public school and frequently, actions that I couldn't relate to in other people were taken to an extreme and sometimes openly dissected and analyzed by the staff.