Norah McClintock 
Last Chance [PDF ebook] 

Robyn’s scared of dogs-like, really scared. But she agrees to spend her summer working at an animal shelter anyway. (It’s a long story.) Robyn soon discovers that many juvenile offenders also volunteer at the shelter-including Nick D’Angelo, a boy from Robyn’s past. A boy she hoped to never see again. Nick has a talent for getting into trouble, but after his latest arrest, Robyn suspects that he just might be innocent. And she sets out to prove it…