Ehh, my scale goes:
Baby: 0 - 1 1/2
Toddler: 1 1/2 - 3
Little Kid: 3 - 5
Kid: 5 - 13
Teen: 13 - 20
Young Adult: 20 - 30
Middle Aged: 30 - 45
Middle Aged/Old: 45 - 50 (Depends on how old they look.)
Old: 50+
Then again, my scale isn't the global standard, I understand. *shrug*
Also, I don't think I'd ever wear contacts because if I did, I'd likely mess up somehow and hurt my eye. Besides, I like glasses. They allow me to look over the top if I need to, you know, look cool, or something... *shrug* Then again, when I push my glasses up to the point where looking straight ahead isn't looking at the top edge, they touch my eyelashes. If you've ever had that happen to you, you know how uncomfortable it can be.