Files uploaded by multiple users to be shared by other users

Hi, Please advise.

I have been asked to develop a Web site that will require members to sign in, run a blog, have a newsletter and be translated into multiple languages, none of which are a problem. I use Headway as the theme.

I need advise in that the Web site is going to be used by experienced teachers who will upload teaching material themselves to the site and this material will in turn be downloaded by inexperienced teachers to prepare their lessons so in essence they will “teach together”. There will be many users and a vast amount of material. It will also happen that people uploading will download as well. Each user may do multiple uploads or downloads.

I have searched the plug ins and dont seem to find one suitable. Can anyone suggest one?

Thanks