I'm glad you stopped by our site. Here's my thoughts on the letter. Start out by thanking the principal for the opportunity to introduce your child to him/her (if this is your child's first year) or for the opportunity to provide input. I know it seems like sucking up because... well, it is. But you did say the principal is open and it doesn't hurt to play nice. Keep the letter positive and focus on how to get the best from your child. It's okay to mention some traits that clash with your child, just do it dimplomatically. For example, Johnny responds well to quiet redirection, but is frightened by raised voices and loud noises instead of Johnny needs a teacher who doesn't yell.
Be sure to keep a copy of the letter for your records. It could come in handy someday.
Have you checked out www.wrightslaw.com? They have a lot of info for parents and have some articles on letter writing.
