In Ayn Rand's Anthem, why do Equality's teachers disapprove of his quick mind?

Within the first few pages of Ayn Rand's Anthem, Equality speaks about growing up in the society in which he was born. His experiences with teachers during his schoolboy years are significant to the story because this is when he learns that he is different from other boys. For example, he remembers that lessons in school came to him easily. In fact, he is so bright in school that he can predict what teachers say about lessons before they finish explaining certain concepts. Being intelligent and able to learn things easily sets Equality apart from his brothers, which also places a figurative target on his back because it is a crime to be different or better at anything in this society.
Equality isn't just different, though; he is superior to his schoolmates. Superiority is worse than simply being a little bit different. Superiority means that Equality has in him the capacity to become someone great, and this scares his teachers. Again, in this entirely equal society, no one is allowed to be better than anyone else. Equality explains as follows: 

"It is not good to be different from our brothers, but it is evil to be superior to them. The Teachers told us so, and they frowned when they looked upon us" (21).

Equality also receives "lashes" when the teachers feel as though he is exhibiting any superior traits at school. The teachers try to keep Equality's individuality and intelligence under control so he cannot upset their society with his differences. The whole society exists under the following motto:

"We are one in all and all in one.
There are no men but only the great WE,
One, indivisible and forever" (19).

Their government, which favors society's needs over those of individuals, does not like to see anyone thinking or acting differently from the others. Individuality leads to self-promotion, ambition, and inequality; therefore, the teachers, who are an extension of the government, do their best to squash Equality's divergent tendencies in order to keep their society functioning as one equal whole.