Building a quizzing system for multiple classes and teachers. 
Game:
A set of MCQ Questions that a Player can answer. 
A Game will be assigned to a class or multiple Classes by a Teacher.
Player: A student(user) who plays the Game
Class: A Group of Students

Flows:
Displaying Class Level Report
Teachers should be able to see aggregated class level data how their class performed across all the games assigned to the class.

Displaying Student Level Report in a Class
Teachers should be able to see aggregated student level data how the student performed across all the games assigned to him.