Roller Girl by Victoria Jamieson
For most of her twelve years, Astrid has done everything with her best friend Nicole. But after Astrid falls in love with roller derby and signs up for derby camp, Nicole decides to go to dance camp instead. And so begins the most difficult summer of Astrid’s life as she struggles to keep up with the older girls at camp, hang on to the friend she feels slipping away, and cautiously embark on a new friendship. As the end of summer nears and her first roller derby bout (and junior high!) draws closer, Astrid realizes that maybe she is strong enough to handle the bout, a lost friendship, and middle school in short, strong enough to be a roller girl.
Lunch Witch by Deb Lucke
When Grunhilda the witch is forced to look for new work, she finds a job as a school lunch lady, where she enjoys scaring the children, until a little girl with thick glasses named Madison comes along and sees through her act.