I think 'The Outsiders' could be considered similar. It focuses on a group of young people and their struggles, relationships, and the society they are in. In 'skins the novel', there might be similar elements of youth culture, friendship, and the challenges that come with being young. Also, 'Looking for Alaska' has that exploration of teenage angst, relationships, and self - exploration which could be related to 'skins the novel'.
Well, 'To Kill a Mockingbird' has some similarities in the sense that it shows the growth and understanding of its young characters in a complex world. Just as 'skins the novel' might explore the lives of its characters in depth, this classic does the same for Scout and Jem, dealing with themes of morality, society, and family. And 'A Tree Grows in Brooklyn' is also a good comparison as it tells the story of a young girl growing up, facing various challenges, which is somewhat like what 'skins the novel' might be about.