First of all, you have to decide what chapters to talk about in that grade, treat teachers as children, teach with them, interact with them and ask them questions. Pupils, don't speak too fast. Speak slowly. Explain examples, give exercises, leave homework, and pay attention to links. Keep your speaking speed moderate. At home, you can also surf the Internet to see how others attend classes. You can also prepare props or something if necessary. I tried to talk about the topic in a training institution, but only in junior high school. Good luck.