You know, if he has just moved up from the lower sets, then he will not have had the same in depth teaching as the rest of the set.
I hear all of the education experts on here cry out "the curriculum is ubiquitous ". But you know that it isnt right? That is why there is streaming in the first place. Lower sets are taught less detail and complicated issues are skimmed over.
How do I know this? I moved my DD school at the start of yr8 due to bullying. Despite her having been in all of the top sets and special streams throughout her education, she was put in the lower set 3 for streamed subjects, maths, english, science, French.
Through laborious politics and other such nonsense, it took almost the full year to get in to the top set in science. It was made even more difficult by the fact that she had not been taught enough detail to pass the upper level assessments her teachers kept putting her in for. They all knew she didnt belong in those sets as did the pupils who laughed at her every time she answered a question because of her vocabulary. She received the second highest results across all of her assessments in the entire school last year.
Once in the top set she would come home crying because the teachers assumed that she would know what they were talking about, even though she had not been taught it in the lower sets. She is begging to go back to the lower sets, not because she is incapable, she just feels like she is too far behind. She has had sanctions and has been told off in front of the whole class in terms of not deserving her top set place (because for the first time ever, she forgot her book).
If he has just moved up sets, he may be out of his depth and perhaps the teacher could ASK him if this is the case.
A different perspective from my school years is as follows...I was top set everything too, but I was bored stiff. The teachers would focus on the favourites and ignore others. For my maths teacher I was an other.
I once sat with my arm raised for an entire lesson, whilst getting on with all the rest of the work, finishing it , checking it, waiting. After 45 minutes he came over and I really couldn't remember by that point why he came over.
Everyone was getting ready for the bell about to ring and I was quite embarrassed so I asked him if he lost a hair every time he was wrong (he was bald).
I know this was wrong but after months of watching him help his favourites, I was frustrated.
So disruptive behaviour is sometimes not all about the little SID but due to teachers failing to communicate respectfully.