I'm a mother of two. My 8 1/2 year old son is having problems at school...has been for the last year or so, but only this year has his teacher brought it to our attention, and let us know how bad it has become. As a parent, I agree with the others....let us know as soon as you realize something is wrong, and it's more than just an occasional thing. The teachers as professionals are more aware of what is "normal" for a classroom setting, and are exposed to more children, so (in my mind at least), have a much better idea of what's going on that the parents probably do.
We're not sure what exactly is the "problem" with our son, but it seems to be what his father has/had. At the very least it has aspects of ADD/dyslexia/visual learner...it may not be any of these things, but then again...it might. Never rule anything out!
I can never thank his teacher enough for bringing this to our attention....his other teachers made reference to aspects on his report cards, but never really talked to us much about it, and certainly never said "well, it could be this...." I would never have thought of dyslexia until she mentioned it.
To a large extent, our childrens teachers are our lifelines, and we need to work together to make sure our children get the best of the school experience that they can...education...interaction with peers...etc.
(sorry for the longwindedness