Not in high school. Be careful in class and have a rest after class. Don't relax too much on weekends, you still have to finish your homework. Ask more questions, don't be shy to ask the teacher. I feel that students don't like to ask teachers now, but like to ask classmates. You don't need to buy too many reference books, just listen carefully to the college entrance examination in class (and why did you send your questions to the operating system? . . )