"Post-teaching" means that teachers guide students to discuss the problems exposed in students' self-study and the mistakes in practice, and "soldiers" teach "soldiers". Students who can teach can't, but teachers only evaluate, supplement and correct. In this link, teachers must fully trust students, and teachers must never take over the problems that students can solve by themselves. For example, when reviewing the lever part, it is difficult to have a lever balance problem. I let the students discuss it first, and then let the students talk about it. Then, a Yu Meng talked about a method from the balance condition of leverage. Zhang Yonggang gave another method to solve the problem from the angle that the power arm is several times that of the resistance arm, and the power is a fraction of the resistance, which can deepen their understanding of knowledge.
"In-class training" is to let students finish their homework independently in the classroom and carry out strict training, so as to reduce the plagiarism of homework, improve the quality and reliability of homework, make it easier for teachers to know the students' learning situation in time, provide targeted counseling, increase the accuracy of counseling objects and effectively reduce poor students.
"Learn first, then teach, and train in class" is a simple sentence, but it contains advanced teaching ideas: "The teacher's responsibility is not to teach, but to teach students to learn", "Learn before teaching, and promote teaching by learning", so as to achieve the best review effect.