Kindergarten is meant to be enjoyed. It isn't normal for a Kindergarten kid to be unhappy during the day. Sure a Middle school should be mature enough to handle that his days have high and low points, but that is asking a lot of a kindy kid.
It may be the the teacher is seeing this and feels bad and hopes for ideas on how to change this?
On the other hand, it may be behavioral issues. If so, I love that book 'Transforming the Difficult Child Workbook' by Lisa Bravo and Howard Glasser. In addition, he needs to be in a classroom with kids who are similarly 'ready to learn' - MAP scores are great evidence of this. It's normal for school folks to be worried by the behavior and not want to place a kid with older (better behaved) kids, but if it gets to the root of the cause of the behavior problems, then it works quite well.
It may help to encourage a 'scientific' approach - create several hypothesis, construct tests to see which one is true, and then evaluate the results.
Prepare for the meeting by writing up a few stories that help the teacher see the child you see - some about the precocious aspect, some about the 'burn to learn' some about how school makes him feel.
Keep us posted,
Grinity
