Disability

My school has classes for children with disabilities. Ranging from severe (physical impairment, deformities, intense speech impairment) to moderate (slight speech impairment, inability to understand social situations/etiquette ((as in their behavior is more along the lines of a 4 year old or 7 year old)) 

The kids that have some disability but can function like any other person are not involved in these kid's classes. 

Now here's what I'm agitated about. Everyday before school, before both lunches, and after both lunches, their class (it's called the special Ed class, we call it Ed for short) cleans everything. The school has them cleaning tables, sweeping, mopping, cleaning windows, picking up trash on school grounds, doing the recycling and taking out the trash. Maybe I'm missing something, but it angers me that these students who could be learning, who could be spending the half of their day that this cleaning takes up, learning how to interact with people, could be taught how to solve problems, how to be a person.

They aren't allowed at the most basic of school events, they're monitored everywhere, I tried having a conversation with a sweet boy that was in the class but one of the teachers/monitors quickly ushered him away from me. They aren't stupid. They aren't incapable. Why are they being treated as janitors??

Am I missing something? Is there something that I'm not seeing here? I just feel like they're being taught that all they are good for is wiping windows and tables.