One of our lecturers did something similar, but with class grades. They started from a complete list of grades in Excel, and for each student, deleted all grades but that student's grades and then saved a copy.
Unfortunately, they did this without disabling the Excel feature that saved undo data in the file, so anyone in the class was able to hit Ctrl+Z a couple of times and see the entire list of grades.
Unfortunately, they did this without disabling the Excel feature that saved undo data in the file, so anyone in the class was able to hit Ctrl+Z a couple of times and see the entire list of grades.