There is also a convention for many to many but I don't know if this is required
You call the mapping table the of the two tables and end it with Map
Teacher -> TeacherClassMap <- Class
If I am I because I am I, and You are You because You are You, then I am I, and you are you. But If I am I because You are You, and You are You because I am I, then I am not I and You are not You. -Rabbi of Kotzk