Solidity
Novelette 16,528 words Recommended by 6 award/anthology sources
"The air in the classroom was warm and still, the teacher’s voice a lullaby, with stress falling on syllables like the patter of sparse, heavy raindrops on the roof tiles. Omar fought to keep his eyes open, reading the words on the blackboard backward to sharpen the soft sentences into dnim sih rof selzzup gnizzub."
Quasar links out; the story lives on Asimov's, where the author gets the click.