Teenage – being of the age 13 through 19; “teenage mothers”; “the teen years”
teen, teenaged, adolescent
young, immature –

(used of living things especially persons) in an early period of life or development or growth; “young people”

Teenager is the age between 13 and 19 years old.
: of, being, or relating to people in their teens
— teen·ag·er noun

Psychological changes and movements of revolution always targets the teenager stage, due to the state of adolescence that occurs during that time.

Teenage is the stage in one’s life which falls during the process of adolescence.