Today's teenagers grow up more slowly. Researchers looked at 8 million teens over the past 40 years. Today's teens are less responsible than teenagers from the 70s, 80s and 90s. Today's 18-year-olds are like 15-year-olds used to be. Teenagers today take fewer risks than they did before.

Today's teenagers take longer to do things their parents did, like dating, working, driving, and renting their own room. A professor said they have a, "slow life strategy". One reason for this is many teenagers live in the Internet and not the "real world". Another reason is parents do too many things for their children.