In this third book in the series, Julia starts sixth grade. Referred to as "Sixlets," the new middle schoolers live in fear of the "Crazy Eights," two years their senior. Julia's teacher, Mr. Lamonte, says, "You are now middle schoolers. Controlling for variables will help you manage your many new responsibilities. Let's all try to rise to the occasion, shall we?"
Julia takes his "controlling for variables" suggestion to heart, even finding ways to avoid the scary third-floor bathroom where the eighth graders hang out. But, from her aging dog to her sullen, third-grade reading buddy to a (seemingly) hostile "Crazy Eight" nemesis, Julia soon learns that some things can't be controlled, no matter how hard you try.