When a new girl with strange habits joins the eighth grade, it will be up to Lilly to solve the mystery.

After having put her vast medical knowledge to good use to save the life of a boy with juvenile diabetes, Lilly Stone is ready for her next medical mystery. When she meets new girl Kay at the start of the school year, she is determined to figure out what makes her tick, as her strict habits and aversions to noises and smells have attracted the attention of the school's bullies. What could be the cause of Kay's behavior? Enlisting the help of her friend Aubrey and boyfriend Ray, Lilly looks for a way to help Kay fit in. While doing some research, Lilly stumbles upon Asperger's Syndrome. Could Kay have Asperger's?

While piecing more clues together, Lilly and Aubrey teach Kay the rules of eighth grade. During one of their sessions, they uncover something else extraordinary about Kay. But her gifts are misunderstood and misdiagnosed by her peers at school and her doctors. In a moment of inspiration, Lilly convinces Kay to participate in the school spelling bee and talks her into a makeover. While Lilly works to showcase Kay's talents, she senses a change of heart among their classmates. And when Kay decides to stay true to herself, she offers the whole community an important lesson on accepting differences, leaving Lilly to consider who was teaching whom all along.

Embracing nonconformity, Different is an engaging story for middle grade readers, exploring the social pressures of fitting in at school.