I think there are teachers with understanding of SEND, but maybe insufficient knowledge. Every child with SEND is different, has different needs, requires different management ( for want of a better word) and has different responses.
Years ago the CoP for SEN stated that the expectation was that 3 children in a class of 30 would have needs sufficient to warrant additional support and a smaller proportion would require a statement, now EHCP. Clearly, the numbers are much greater now and I’d agree that it’s closer to 25% than 12%.
At the beginning of this century, funding for SEND could be diverted to other needs in schools. I made myself unpopular by insisting that the SEND budget be spent on the children it was intended for. There are certainly children who are ND and have difficulty coping in school and their response is to challenge. There are children who are NT and display behaviour that’s difficult to manage in a classroom and impacts on the learning of others.
Again, in the early 2000s, my school had an inclusion room, staffed by senior staff. A child who was not responding to the usual sanctions could be sent, with work, for the remainder of the lesson. Of course, the work hardly ever came with them, certain children would ‘arrange’ with their mates to be sent there and as a member of staff, its intimidating to be faced with 20 people who have no desire to be there, or even in school. I had six lessons a week in there and the only time I’ve had to hide my tears is in that room.
It’s complex and very difficult, but it’s about appropriate funding, appropriate skills, appropriate placements, support services of all kinds and parents who are invested in the education of their children and support them and the school they attend.