I was put in special education program for my dyscalculia (Basically the math equivalent of dyslexia), and it was called an IEP ( IEP stands for Individualized Education Program). Teacher aids, administrators, and principals would arrange meetings to discuss what kind of education I would get for the school year. Typically my mother and I would both go.
Every year I went to those meetings, I hated it. I couldn't learn math as fast as everyone else, so that made me out to be some-sort of outcast and problem child. In these meetings we would discuss my behavior and then we would discuss what kind of aid I would receive in regards to my "disability" for the school year.
For years I felt like a complete failure because I couldn't learn math concepts as quickly as everyone else could. Because of the IEP, the school wouldn't let me take honors or foreign language classes. What's worse was that other students knew I had an IEP, because the teachers would speak to me and bring me fully-written notes.
They also put me in slower classes. These classes weren't special ed per say, but they were definitely made for students who learned more slowly.
The kids in these classes typically had ADHD, minor autism, minor OCD, behavioral problems, or it just took them longer to learn.
It wasn't until my junior year at a new school that I convinced them that I no longer needed it. My self-confidence went up, I had the best grades ever, and I didn't hate school anymore.
TLDR: Special education is good for students with full-blown autism. Anyone who is competent and self-aware should not be put in that system.