The secret's in the hyphenation. According to the Oxford Dictionary, make-up meaning 4 is
- (North American count noun) A supplementary test or assignment given to a student who missed or failed the original one.
‘I would have flunked the course but she let me write a make-up’
This tallies with my understanding, that a make-up is equivalent to the British English resit: you fail an exam and have to repeat it. It is probably not ideal for this situation, where the class was cancelled for all students due to circumstances beyond anybody's control.
A better term to use would be reschedule, which would not imply any failure on the part of the students. You can optionally specify the new date:
Our class on Monday was canceled due to heavy snow, so the teacher rescheduled it [for next Friday/ for the 16th February].