School multisite – students have individual blogs, teachers need editor access to all of them

Hi all, not sure the easiest way to do this but I’ll explain what I’m trying to achieve and hopefully you can tell me how I might get there! It’s outsmarted me so far.

I’m trying to set up a school multisite (though am open to BP or other extensions) that will work like this:

– Every student has their own blog that they are an author on (done via the Batch Create plugin)

– Every teacher has the ability to edit pages/posts on every blog on the network (effectively adding them as an editor to every single site – and this is the problem)

– Teachers can also edit curriculum blogs for that have content the students can access

– I’m currently using the Multisite Privacy plugin and would like to cut visibility of students’ sites to registered subscribers and above only, but as it stands teachers wouldn’t be able to see those sites at all, much less edit them.

We originally planned to have teachers able to add Comments to pages/posts on the students’ sites, but now the school management says teachers should be able to edit pages in order to put annotations ‘inline’. Currently we are trialling it with a basic multisite but the problem comes when you try to scale it up:

How can I add 50 or so users as editors to around 1200 blogs? Or is there another way of setting about this? Am I coming from the wrong direction? Would BuddyPress and its Groups give me a way of doing this?