Hi. Dont want to be too cynical, but my experience is that no-one will arrive on a white horse to rescue your son or you - schools are run by the county councils who want to provide the minimum to the maximum number of children due to budgetry concerns - if you want your son to get the right support you will have to fight for it. Forget about making friends or influencing people, as headteacher told me, the parents who scream the loudest are the only ones who get support for their kids - the rest fall through the cracks - of course she only told me that as ds was moving up to secondary so leaving her school!
Teachers and SENCO's do not have the training in SN you think they would have. A statement places a legal requirement on your local authority to provide specific support for your child, which is why they usually have a policy to block any attempts by parents to have their child assessed. Fortunately, there is a step by step legal process to force them, if you have the evidence to support your case, to assess - but no-one at the school, CAMHs or LA is likely to tell you about it!! Contact IPSEA (details online) who are a SEN advice line (sometimes hard to get through but oh, so very worth it!!) who will walk you through the process, one step at a time - not just for statementing but on dealing with school going through all the stages.
If you are thinking of going for a statement, once you let the school or LA know, they tend to circle the wagons and become very obstructive so use this time to get them to talk openly and gather info - use email or letters when contacting school so you have a record, or email after conversation to confirm discussions, keep a journal of every comment, incident etc - all of this is useful evidence. Keep a close eye on attainment grades as they are required to ensure that your child maintaines the same or better rate of progress - so if reading age is not going up by 12 months per year (as chrono age is) child is falling behind, if subject grades do not go up by same rate, stay the same or even regress that is brilliant evidence to force assessment (although my ds's school tried to hide that!!).
Not sure how much I can post as never done this before, but lastly, if you can afford it get independent assessments done - speech and language and ind. educational psychologist. LA wont like it and may refuse to accept it but a Tribunal will accept it - oh and dont be scared of a tribunal, if you have an obstructive LA you have no chance of getting them to agree to anything, at least at tribunal (which is totally unbiased) they go on the evidence so you have at least 50/50!
One last thing - we had a brilliant ed psych called Mike Davies who is a consultant educational and neurological psych with over 25 years experience with AS I think, and on the expert witness list (so his evidence far 'outweighed' LA's ed psych) who helped ensure my son secured a place in a fantastic residential special school - a first at that school although it is in our county! His details are also on line - I hope it is ok to post that??
Not trying to be too militant, but after years of trying to get schools and LA to do the right thing (cos this is Britain right? We look after our kids, dont we?) realised that I had wasted so much time and wished someone had told me there is a process, you just have to know it and 'they' rely on us parents not having that knowledge!
Good luck!