So, so good. In the summer before starting junior high, Astrid discovers roller derby-- and assumes her best friend Nicole will go to derby camp with her. Nicole has other plans with another friend, though, leaving Astrid on her own for the first time since second grade. At practice, Astrid quickly discovers that she's not a good skater -- but also that she loves derby, and there are others on the team who want to be her friend. 
 Friendships change and grow over time, but it's particularly hard to deal with that in middle school. Roller Girl handles this transition with proper gravity and humor, appropriate to the middle school audience and the adults who will also read this. Should be in every teen library!