SAAR Learn holds courses, the cohorts running them and the people enrolled. Lessons and coursework go through review before publication, so a half-written assignment cannot appear in front of a class by accident.

A course is built from modules; a cohort runs it in a term with an instructor assigned to each offering, and learners are enrolled against the cohort.
A lesson or piece of coursework is a draft, then awaiting review, then approved or sent back. Only approved and published material is visible to learners, and each decision is kept with its comment.
A practice task has a due date and no marks. A graded assignment is out of something and cannot be saved without it. Late work is accepted and flagged rather than silently refused.
Resubmitting edits the existing submission instead of creating a second one, so a learner never appears three times with three marks. Grade bands are yours to define.
Create the course and its modules, then the cohort and term that will run it.
Draft lessons and coursework, then send them for review.
A reviewer works the queue, approving material or returning it with a comment that the author can read.
Learners submit, you grade against your own scale, and returned work can be reworked.
Not without a review. Material is only visible to learners once it has been approved and published.
Every decision is kept as its own record, so the author can still read why it came back the first time even after it is approved.
By default it is accepted and flagged as late. You can close a piece of coursework when you want submissions to stop.
You define the grade scale and its bands yourself; a graded assignment must say what it is out of before it can be saved.
Courses, coursework, submissions and grading, with an approval step that actually holds.