DS1 has always been a very good student; self-motivated and hard-working.
Since the end of Y8, he seems to have become like two different people.
In subjects he likes, such as Maths, Science, History (yes, I know it sounds like a line from TBBT theme song), he is still really motivated and putting in a lot of effort, getting level 7s.
In other subjects, he seems to be trying to put in the minimum effort that he can get away with. In English, he was asked to redo an essay as the teacher knew he was capable of much more. Food Tech is similar.
In others, he seems to have just given up completely. I just had an email from his RS teacher explaining that he got a level 5 in his latest assessment. Six months ago he was getting level 7s in RS. Geography is similar.
I asked him about it, and he says that he just has very little motivation any more, especially in the subjects he knows he won't be doing for GCSE (WTF happened in English, then?). He wants to be a primary school teacher, so does have a possible career to aim for. I feel so frustrated with him, as he has the aptitude and the privilege of a good education.
Has anyone (teacher or parent) successfully dealt with this problem in a student? What worked?