Folder Naming Convention

I am trying to organize my folders by name with the following syntax "A-1", "A-2" all the way through "A-99". When get up to "A-10", "A-2" is then listed after "A-10" because of the formatting. I tried to get around this by naming the files "1 - A-1" etc. but this same problem still persists. Please advise asap.