Our administrator has it set up so that we can share the Calendar and Gmail, we can send Gmail outside, but we cannot include any outsiders in the documents. It is possible to change that, but that's the way our administrator has set it up, that it's totally a private environment.
We use Gmail, we use Calendar, we use Drive and Drive includes presentations, although their presentations aren't great, documents and spreadsheets, workbooks, which are multiple spreadsheets. I think that's it. But the presentation is not great so we don't use it very much.