For TANF, FamilyCare Assist, Family Assist, and Moms and Babies, there is no upper or lower age limit to qualify as an adult.
For TANF and All Kids, a child must be age 18 or under. An 18 year old child must be in full-time high school or an equivalent residential program to receive TANF. For All Kids, an 18 year old does not have to be in school.
See PM 03-04-00 for more information about age and student status.