I think I got the gist of that, but it appears to be in some kind of code. Can you translate for me please?
ADHD - Attention Deficit Hyperactivity Disorder (previously ADD) - behavioural disorder usually characterised by extremely short attention span, impulsive behaviour, lack of thinking before acting / speaking. Often dismissed as 'bad parenting' by people who haven't met proper ADHD kids and seen the change when they take Ritalin (other ways of drugging children are available).
With that said, a lot of allegedly 'ADHD' kids, the ones without a proper diagnosis by a psychologist, are just naughty and have spent their whole lives staring at screens. Sitting in a chair quietly and writing is something quite alien to them, as is being told "No".
ODD - Oppositional Defiance Disorder - where the child has a compulsive need to argue back. Not the same as simple gobbiness / temper tantrums where kids will argue back with things they think are unfair. The ODD kids will argue about anything, up to and including what colour a door handle is. Quite rare, I've only met one with a proper diagnosis.
A statement is an official declaration that a child has moderate to severe SEND issues and the school are mandated to provide a certain number of hours every week with direct support (usually in lessons via a TA or LSA). Incidentally, statement is the old term and it's now an EHCP (Education, Health and Care Plan according to google) although I've also heard it referred to as an Education and Health Care support Plan.
LEA - Local Education Authority - back before academies were a thing, almost all state schools were run by a branch of the Council called the LEA. Parents could complain to them if they didn't get the 'right' answers from the school. As academies are outside the LEA (and effectively private businesses) it's not the threat it used to be.
And from above, TA = Teaching / Teacher's Assistant, another adult in the room who goes round helping individuals. LSA = Learning Support Assistant, someone with SEN training who is there to help a specific student (who usually has a statement / EHCP). Both are wonderful people who do a very valuable job for abysmal pay and spend most of their working day keeping the ********* busy so I can actually teach the ones who want to learn.
Edit - the above waffle explains what the TLAs mean, Grumpy's post is an accurate assessment of the overall situation