Do you live in the US? If so, does your state mandate IEPs or anything at all for gifted children?

Your son's teacher seems to recognize some important things about gifted kids. You might try to send her an e-mail (so she has time to think) saying that there are really two issues: grade-level or below writing and beyond grade-level reading/math. Does she have any suggestions for addressing both things?

Maybe you could suggest that holding your son back in reading and math because he has age-level writing isn't the best solution. Perhaps the school could find a way to help him work on K-level writing while making an accommodation for reading and math.

Quote
She also said "bright kids" like to learn. She said "he doesn't seem motivated to learn" so she wants him back in a K class.

Hmm. It's really great that she recognizes this idea. Maybe you could ask her how he'll learn from reading class in Kindergarten. Think about how she answers and then ask for her suggestions on how to help him. Does your school have reading buddies? Maybe he could have a reading buddy in a higher grade.

Just my 2c.

Val