NOT before 10 years of age, if you ask me. My sister's only almost 8, and she wears them with t-shirts, but only if we are staying home for the day. Other than that she wears them over leotards for gymnastics.
well i mean any age really but i always make sure its at least 1 1/2 through 2 inches below the bottom of my butt. but lately my boss has been makeing me where shorts so shorrt litterally half my butt is showing.