Under the circumstance that the primary and secondary education levels have failed to adequately prepare a student for tertiary level, I think your idea would be unfair.
The university teaches what it teaches; it exists as a place of higher learning. If the student is unprepared for that, they are unprepared to attend. It's not university's job to fix shitty high schools' teachings and redo lower learning. Go get a highschool tutor if you need that.