Drupal and advanced user rights

I work for a webagency, and I have to develop an intranet/extranet app to be used as sort of a DMS (Document Management System) for a high school. Some of the requirements of the projects are using Drupal CMS and having advanced user rights. Let me explain :

The professors can post only for their students, and the students can only read articles from their teachers. There will be a lot of groups, like for example :

• Sports option
• Seniors scientists
• Juniors litterary
• ...

Sorry if this doesn't make much sense, but in France, the school system is very different from the USA. Basically, let's say we'll have one user group per class, and 1 for all the teachers, and 1 per "option" (we can take options to earn extra points to help us get our diploma).

The problem is, noone in our office knows how to use drupal. I have to make some research, and I found a couple of modules that could do the deal, but I couldn't manag开发者_如何学JAVAe tu make them work properly. Do you know any module that would work in this particular situation ?

You will have a lot of group overlapping, so when a user is a member of teacher, sports ... how do you know which group he posts for?

The solution instead of creating a ton of groups, is to create different content types, one for each type. Then you only have to manage the permission, which users should be allowed to create and view the content.

A combination of CCK, Views, Content access should be able to do it for you.

Organic groups like Fabian suggests could also be useful, but it might be better with a simpler solution in this case.

It sounds like Organic Groups would be useful for you.