Roles and permissions

I would like my front page roles set so that whenever I post an update to the news forum everyone receives an email.

I thought that was a default for the past month and realized that people have not been receiving the emails because none of them are considered to be students of the front page and therefore are not enrolled in the forum (though I clicked forced enrollment).

Even when I set the default role for the front page to student, when I check to see which students are enrolled, the number still says 0. I can add students manually, but that means that I will have to hunt through all of the students that have ever been registered for any class and pick out the ones who still are registered by hand. I would also have to go in and add new people by hand as they register for classes.

So, I am wondering if there is a simpler way to do this. How do I set my front page roles so that everyone who is currently enrolled in the school is automatically a student of the front page?

Thanks in advance!
Ameerah