I like Herbert Kohl, and although most of this book missed the mark for me, I really appreciated his thoughts about "cultivated stupidity" among students (and teachers) in schools. He argues that when the school system is stupid, then we are stupid, too.
I call this the "script" of schooling. Everybody has experienced education, so everyone feels like they know what it should be, and even though school hasn't always been good and democratic and liberating, most of us adhere to the system. For marginalized students, this means playing the role of the clown, being stupid in class -- with the teacher, usually white, getting angry.
Another great essay was "Topsy-Turvies," in which Kohl talks about language in the classroom. He says that teachers must listen to what they're saying, perhaps even more than what the students are saying. If students aren't facing you when you're teaching, it's not that they're bad; rather it's that what you have to say isn't of value.