There are many versions of junior high school mathematics, but the main ones are Beijing Normal University Edition and People's Education Edition. I am familiar with Beijing Normal University Edition. I suggest you talk about quadratic function, because it is easier to talk about and it is also a key content of the senior high school entrance examination! Quadratic function should start with the definition, combined with its image analysis properties and error-prone points, plus some easy exam questions! The large class trial lecture process begins with introduction (starting with reviewing the function once, plus the scores and importance of the senior high school entrance examination), and then combines the nature of numerical analysis (adding one or two examples to investigate the nature) after drawing, and summarizes the homework after class!

The cohesion and coherence of each knowledge point need your own characteristics.