DS is in year 9. At primary he was quiet, nervous, often burst into tears if he couldn't find things, was good at maths and english but quiet. There were only 14 boys in his class including a few strong groups of friends and a few outliers, the outliers stuck out. He went to a big high school and hardly has anything at all to do with the children from his primary school.
His first term was traumatic, getting on the bus, losing his timetable, finding his way round, losing his jacket and PE kit (numerous times), bursting into tears in one class because he forgot his homework. With every new thing, he had a new hurdle to face. His tutor was an angel, kept an eye out for him, had a word with all of his teachers to let them know he was a nervous child and on one occasion emailed me to let me know he was OK when he went to school having no idea what class he was supposed to be in.
He made a few connections in his first few days which he clung to for a while but these were almost all replaced by real friends by January. Sadly at the end of year 7, two out of three of his best friends moved away, I was devastated but he has been fine. He has made new friends, they are a bit like him, a mixture of intellectual levels, he has some friends who play football together, some who he plays with on the XBOX on line, some who play board games when they get together.. some kids have come in and out of his circle but no major dramas that I have been aware of from his side... though I do know some of the other children (girls mostly) have had some challenges..
He has found his tribe, teachers like him and praise him for who he is, which never happened in primary school, he has a range of personalities he seems to show in different classes, from one of the boys who chats and mucks about a bit to completely and utterly engaged. I think all of this is OK, he is trying out his wings and I think his exploration of his social side is an important part of his development which was somewhat restricted in his small primary as there were fewer people to spar with, as it were.
He is happier and quietly confident in himself though still nervous in new situations but altogether, high school has been a good change for him.