They can't read long form information because they didn't want to before high school. Now they can't without a great exertion of effort.
They can't write because they don't read, which is where it is easiest to learn new words.
They think social studies is boring because it's a lot of reading and writing. That the class usually focuses on stuff that happened too long ago to be visible in their lives doesn't help.
They don't understand mathematics because their earlier instructors taught it as algorithms without context, the beautiful axiomatic nature of mathematics is never revealed.
By contrast, everyone can do PE. Even kids who stay indoors a little too long, slowly giving themselves radon induced lung cancer. If you're good enough, you can even get a scholarship to play on a college team.
It's no wonder in most schools so much emphasis is put on sports games.
So what do you get when you have a bunch of illiterate teenage prisoners in a room trying to read Shakespeare?
About the same thing you get when you have a thousand monkeys try to write it.