In previous years, I took exams after entering the South China Campus. According to the parents and teachers of the school, since Shouchun implemented small class teaching last year, the so-called key classes or parallel classes have become obvious. I have asked many people, including relatives who went to Shouchun's house, that there is no such thing as a key class. If so, it may be in terms of teacher allocation. Maybe a teacher teaches math well, and which class teacher to take. There is no difference in other aspects.