My son entered preschool reading quite fluently. The Montessori school he attended thought he was *behind* in reading because they required him to do "learn your letter" exercises that he'd mastered over half his life ago, and so he simply stopped going into the language arts section completely.
We had a somewhat better experience with our DD. I'd heard about situations (in both Montessori and conventional preschool/K) where the teachers never realize that the child can read, so I was explicit about her abilities during the admissions interview. I explained that she started to read at age 3, and mentioned the titles of some books she was currently reading. They said that they would still present all the introductory materials in sequence, as was their policy, but it would just be a quick review to make sure she knew them; she'd be able to move ahead almost immediately. This did turn out to be the case. Unfortunately, since it was a primary-only school, their language materials maxed out at around 2nd grade level, so she soon ran out of things to do in that area. In hindsight, I wish we'd picked a school that went through elementary, so they would have the option of bringing in more advanced work.
It does seem a bit crazy that the teachers wouldn't clue in that a child was far ahead of what they were teaching, but the 3-6 curriculum is broken down into so many small, specific tasks that I can kind of see how this could happen, especially with a child who isn't inclined to speak up much (which would describe all of mine!). OTOH, if you told the teachers up front that your son could read, and they didn't pay attention and check it out for themselves, that would indicate mighty poor observational skills on their part. I think they might have to go back and spend some time working with the sound boxes, to improve their auditory discrimination skills.
