用户到用户数据库对象结构

What is the best practice to structure my objects in my database in a Teacher to Student application? To be more specific, a teacher will have multiple students, and students may have multiple teachers they will interact with. Right now, each class a teacher is instructing has a "class id" and when a student enrolls, they add that same class ID to a list in their model. When a teacher wants to view a roster, I use What is the best practice to structure my objec