I think it is a good video class about classroom English. you will have some very useful expressions about when you are in class.

(Classroom English: Vocabulary & Expressions for Students

Are you the new student in your English class? Do you understand what your teacher is saying? In this lesson, we will go over some of the vocabulary, expressions, and questions that you might hear in class. What do you say if they are speaking too fast or if you didn’t hear? It can be stressful to ask questions, but after this lesson, you will be more confident participating and interacting with your teacher and classmates.)