Kids vs. parents! An epic treehouse sleepover! An awesome group of friends! An exciting new book from National Book Award finalist Lisa Graff. Winnie's last day of fourth grade ended with a pretty life-changing surprise. That was the day Winnie's parents got divorced and decided that Winnie would live three days a week with each of them and spend Wednesdays by herself in a treehouse between their houses, to divide her time perfectly...