Names for different age group

http://theelderlies.wordpress.com/2006/10/02/age-by-decade/ offers

• Denarian: Someone age 10 to 19.
• Vicenarian: Someone in his or her twenties.
• Tricenarian: Someone in his or her thirties.
• Quadragenarian: Someone in his or her forties.
• Quinquagenarian: Someone in his or her fifties.
• Sexagenarian: Someone in his or her sixties.
• Septuagenarian: Someone in his or her seventies.
• Octogenarian: Someone in his or her eighties.
• Nonagenarian: Someone in his or her nineties.
• Centenarian: Someone 100 or more.
• Supercentenarian: Someone 110 years old or more (no upper limit).

This does not address 0 to 9, I offer wee-uns.