An alternative approach is to keep a record sheet for each pupil, on which the teacher ticks and initials the relevant boxes when the pupil has completed a particular piece of work.
Storage can be a problem.
It is still difficult to collate the information. One way of overcoming the last disadvantage is to create a database or spreadsheet to record the work that pupils have completed. Using a spreadsheet, for example, it is possible to insert formulae that will count how many Units a pupil has completed, and to show you this information at a glance. You may find it hard to persuade staff to enter the information. A possible solution is to make pupils or students responsible for doing so.