This is not to say teenagers didn't hold incredible agency in other books in the past. Tom Sawyer certainly showed great bravery. And who is to say that Scout Finch didn't change the life and times of Maycomb, Alabama? But young adults are given more and more responsibility in modern fiction.
The Atlantic recently wrote an article about the growing role of teens in YA literature. While admitting that many of today's popular young adult books fall into a fantasy category, "[the books] ask realistic questions about what happens when children take on adult roles." Teen characters are now faced with decisions that affect not only their own lives, but the lives of loved ones, community members, and even complete strangers. From Katniss Everdeen's choice to protect her younger sister in The Hunger Games, to the freshman Frederick who decides that gay bullying isn't right in So Hard To Say, teenagers learn in modern fiction that they have incredible power.
It's not that YA fiction insists that teens will never meet defeat or failure - authors want to be realistic. But, as The Atlantic states, young adult books "emphasize that even when they fail or compromise, teenagers come to independent and important moral insights when they're forced to take responsibility and make decisions without adult support." Today's youth are given encouragement, not guarantees. But all the same, whether it's a simple action or a difficult statement, teens have the inspiration from YA characters to embrace their talent, desires, and influence.
Read the full Atlantic article here.