The direction this thread has taken illustrates my point perfectly. It has been largely derailed by a few posters whose children are more important than anyone or anything else. The OP's question was not "what is your current axe to grind about your child's teacher?", it was "how can parents support teachers?"
Look, education in it's current state is not the best way for children to learn. It is the cheapest way to make the largest number of people literate and numerate and so on. Teachers are professional educators whose job it is to try to instil that literacy and numeracy into your child. We are experts in that sense (and I don't think at any point did I claim to be an expert in any child's particular special need: that would be a bit of a highly specialised and mainly useless qualification).
In any of my teaching groups (and I currently have up to 7 different groups in a day) there will be up to 6 kids with a specific learning difficulty, at least 2 with a neurological condition like ADHD, possibly 1 with ASD, the occasional child with dyspraxia and perhaps one with a physical disability or mobility problem. This is not including the child who has recently endured a trauma, or is preoccupied with their emerging sexuality or the impending divorce of their parents, or whatever.
I will have access to each of those children for 40 minutes per day, in a group of up to 30. I am under pressure from school management and parents to get all of these children to a certain level of attainment. I must keep all of those children safe, my classroom clean, my resources relevant and entertaining. I will do this with minimal expense (I am, eg, limited to 5000 photocopies per school year as budgets are so tight) and often pay for my own resources out of my own salary.
I feel it is important to point out here that I love my job, feel privileged to work with the children I do, and can't imagine doing anything else. However, when a parent has the unmitigated gall to sit in front of me with their child and tell me my class is boring their child because it is too easy, when the parent demanded access to my class precisely because it was easy (aimed at kids with low ability), then that is fucking stressful. When a parent insists on moving their child into my class because of the results my students get, but then refuses to support me when I try to enforce the rules that ensure those results, that is fucking stressful. When I get - and this is a true story - a parent I had never met phoning the head to complain that I hadn't greeted her when doing my grocery shopping, outside of school hours, that is massively fucking stressful.
So I stand by my original remarks.