When Mary Kate Murphy joins a science class focused on climate change, she becomes aware of lots of things she never noticed before about her small suburban town: Kids waste tons of food at school without a second thought. Parents leave their cars running in the pick-up lane all the time. People buy lots of clothes they don’t really need. Some of her friends who live in the city and are bused to her school don’t always feel included. And the mayor isn’t willing to listen to new ideas for fixing it all. Mary Kate and her friends have big plans. And now is the time for the young people to lead and the leaders to follow—or get out of the way.