Blocks

Greetings.

I'm looking to pick your brains about this particular subject. I'm looking for a block that can let students check what has been updated.
Basically I've got a course that has several dialogues and upload files assignments.
Simply put, a student will send in their work and will have to constantly checked if it has been graded or commented.
I thought I could use the "recent activity" block to do it, but apparently if the teacher adds a comment to the assignment, say asking the student to change something, it doesn't get a reference on the recent activity, nor does it giving the student a grade.
It would make sense that it would no?

It also seems something so 'necessary' that I'm sure there has to be a way of doing it without email notifications, we want to keep it all on site.

On a related matter, I want my students to be individuals, but I use the groups for management purposes. The recent activity block has the report link that just let's any student go in and see all the people signed up for the site, something we don't really want people to know. Is there a way to prevent this so that the student only has access to his data?

Cheers and thank you for you help.