Teens and unfulfilled sexual desires

Why has God given teens such strong a sexual drive and no healthy, acceptable way to satisfy it? This just doesn't seem fair. In Bible times people got married at a younger age. As a result, it was normal to have sex and start raising kids before you reached the age of 20. These days, much of society still frowns upon teenagers engaging in any kind of sexual activity. Why has God given us these feelings if we can't do anything about them?