a calendar per user

Hello,

I'm carrying out a website under Drupal for an extra teaching association.
The site consists in managing multiple calendars in the following way:

- each teacher has his planning within his Drupal account
- each pupil has his planning within his Drupal account
- the administrator must be able to allot a teacher to each pupil each time a new request for course is recorded (with compatible days and schedule)

It is thus a question of creating views on multiple calendars. Can Calendar be appropriate, or do I need event module?
What is the best way to realize this (very useful) project?

Thank you very much for your help. (I really need it !)