Growing up is hard.  As girls age, they find different likes, and can start to stray from long held friendships.  In Roller Girl, Astrid falls in love with Roller Derby.  It is so geeky, but edgy at the same time.  Her friend, however, is more into dance.  Their friendship starts to splinter as Astrid pulls more to Roller Derby.  She is not very good and does a lot of falling but she is learning to get up on her own feet and to find the courage to go forth without her best friend.  It also means she learns to make new friends, and in the long run how to be a better friend overall.  This book was a Newberry honor book and it deserves that honor.  It is a timeless tale of friendship and growing up. It shows that growing up, and growing apart is not always a bad thing, but sometimes what is needed to broaden horizons, try new things, and become the person on the outside you feel on the inside.