Recommended e-Mail based learning system

Good day,

We have an online learning program website. We need to set up an email based program, which automatically send out the content of website to students on a weekly bases as they progress through-out the course. We have quizzes to test the students knowledge on the subject. They can only advance to the next unit once they passed the quizzes. As such the e-mail based program needs to be able to track the progress of the students and send the correct e-mail accordingly. Please provide us an answer if anybody has a recommendation of such a program of service provider.

Kind regards,
Christo Vorster