Firebase structure and picking best way to fix

Project Settings

im new to firebase and used to use mysql. also 1st time using flutterflow.
my firebase structure now is:
users: having email, photo, role and many details.
co-curriculum: name, description, week, start_time, end_time, location
brief explain of my application: mobile apps for teacher to take attendance that they are assign in, but they are able to in multiple co-curriculum group.
i should user id list in co-curriculum or co-curriculum id list in users?
or i need to open more schema for student, teachers, attendance.

What have you tried so far?

i already made login, forgetpassword, settings, admin functions for add user, add co-curriculum.

Did you check FlutterFlow's Documentation for this topic?
Yes