Bullying teachers for extra work doesn't sound quite the thing
I disagree with this (well, not 'bullying' as you shouldn't bully). I do think that all teachers/schools should look to meet additional needs of children, be they sn, or being particularly advanced generally, or in one area.
Ds1 is 6, in Year 1. He is pretty average in terms of Reading, writing etc, on target with the rest of the class. What he is not average at is maths, where he is genuinely gifted (I absolutely hate writing that as it makes me sound like the parent from the op, but it's true).
This has not been 'pushed' at all. He started counting things at 1, adding up piles of toys at 2 etc. At 6, in car entertainment for him on long trips is for me to 'ask him sums' to do in his head. Examples would be 657-559, 1069 + 358 etc. He will badger me and badger me to do this, and fire out the correct answer in about five seconds. He constantly asks me to 'teach him more maths' and we sit down a few times a week. We're currently using the simplest parts of the GCSE Bitesize website, and he's presently loving converting and then adding and taking away fractions.
I have had no help from the school whatsoever. What I have had is the raised eyebrow 'mmhmm' stare from the teacher, who told me that yes, she had recognised his ability, he is top of the class in maths and gets harder work as a result - he's now asked to complete worksheets with double figure sums 
He is so, so bored in school when they do maths. He's started playing up and being disruptive periodically (always when it's maths time), and the teachers will pull me to one side to have a word at school end time and tell me that yes, he may find the work easy, but he still has to do it, and we're supposed to discipline him. IF he was having work at his level provided, there would be no issue.
You shouldn't be made to feel like a precious, pushy parent just for wanting a teacher to meet your childs needs, when they are so far outside 'the norm'.