There's 'Stargirl' by Jerry Spinelli. The female characters in the book have unique relationships that are positive and inspiring. It's a book that can be read by all ages and is often available for free in school libraries or through public library e - book services. Also, 'Bridge to Terabithia' shows the friendship between a boy and a girl, but also has elements of the girl's relationships with other girls in a very innocent and age - appropriate way.
The 'Little Women' by Louisa May Alcott is a great choice. It shows the relationships between the four sisters, their love, support, and growth together. It's a classic that has been around for a long time and can be freely read in many places. Another is 'Ramona Quimby' series. Ramona has friendships with other girls that are very normal and age - appropriate.
One book is 'Because of Winn - Dixie'. The main character, Opal, forms friendships with other girls in the story. It's a heartwarming tale that doesn't have any inappropriate content and can be found for free in some libraries or online libraries for kids. Also, 'The Secret Garden' shows the relationship between the young girl Mary and her friend Martha. It's a beautiful story suitable for all ages and can be freely accessed in some e - book collections.