Learner/Course Progress with Reporting

Hey all, I'm new to the group but returning to Drupal after some years!

I'm hoping someone can point me in the right direction for a requirement we have at a large training organisation. I'm looking to use Drupal as a tool to track learner details and progress on courses. Here's the high level requirements:

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Roles:
- Administrator
- Assessor
- Learners

Content Types:
- Courses
--- Modules (courses are made up of multiple modules)
--- Learners (are added/associated with multiple courses)

Process:
Assessors update a learners progress against a module i.e 20% complete. When an assessor has marked a learner as 100% complete against all modules within a course, that course is marked as complete for the learner.

Assessors and learners can see a dashboard to show a learners progress against modules/courses. Assessors can see a roll up dashboard or all learners progress by learner/course.

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From what I know, I think CCK can handle all the learner requirements. The bit I'm not sure about is how to build the course container (to contain modules which in some ways are the same as tasks) and to let the Assessors assign progress to these modules (tasks). The final piece of the puzzle is the whole reporting piece.

So the question is: Does this already exist somewhere???? I've had a good search but haven't seen anything like this.

Thanks for your input ~ Scott