Im not sure if this is the idea you are looking for:
You can in the version I currently have installed use the enrollment plugin to auto enrol students. V 1.83+
I currently have a ldap enrolment working, it reads from 2 OU containers, 1 for staff and 1 for students. The groups are named in line with the course name, if the user is in the group he/she gets enrolled if the course exists, if the course doesnt exist then a blank course is created.
At the moment there is a need for manual admin to pop users into groups but im hoping on working with some people here about a windows script to assign our students into the right groups automatically.
Ill also add we are still in early development stages of our moodle experiance.