It could be said that there isn't really an issue of teaching to the top students, thus the crux of teaching to all lies in whether or not it can reach the middle and lower level students. A large number of facts indicate: today's "top students" may not necessarily be tomorrow's "top students", and today's poor students may not remain so indefinitely. Moreover, the evaluation criteria for so-called "top students" and "poor students" themselves have limitations and one-sidedness. For example, many top students who performed well in school may not necessarily excel in social practice, whereas some so-called poor students in school have instead demonstrated creativity. This shows: only by adhering to "teaching to all", especially focusing on the middle...