The question was to make a online class membership program.

1. We can create a class - Class had a type start time and duration and maxCapacity.
2. Add User to a particular class (user can be identified by email no need to add authentication) - If the capacity is reached then add user to waiting queue.
3. Cancel the reservation of a class for particular user - Only allowed until 30 min before the start time. And if a seat is cancelled and waiting queue is not empty add the reservation for first user in queue.

Only these were the main requirements. User Authentication was not necessary but user identification was needed.