What are the main ideas in Soar by Joan Bauer?

Some of the main ideas in Soar are positivity and inspiration.
Positivity is a major theme in the novel. A person could expect Jeremiah to be upset at the loss of his ability to play baseball after getting a heart transplant; instead, he uses his positive thinking to make his life better and still participate in the sport he loves. By acting as a coach, he's still able to include baseball in his life without the risk of dying. Other factors in Jeremiah's life—like his adoption—that others might see as problems are instead positive and lucky things to the young boy. He can't be sure of his real birth date, but Jeremiah knows he's cared for and chooses to approach life from a positive angle.
Inspiration is another major idea in Soar. Jeremiah uses his positive attitude and hopefulness to inspire the rest of the boys on the team. He encourages others—like the Vice Principal—to help him inspire people he can't reach. For example, when parents are encouraging their children to quit the team because of the Hornets' scandal, Jeremiah enlists the help of Mr. Hazard to inspire the parents to be excited about baseball. Jeremiah understands that a little excitement and hope can do great things.

The novel, narrated by twelve-year-old protagonist Jeremiah Lopper, explores themes of childhood illness and coming of age rituals through the dual prisms of displacement and baseball. When Jeremiah and his adoptive father, Walt, move to a different town, the boy is not apprehensive about fitting in. Rather, his expectations about this new beginning are wildly optimistic. The move coincides with his recovery from heart transplant surgery and marks his newfound opportunity to join a baseball team and try his hand at coaching for the first time.
The reality, of course, cannot match the expectation, but the magnitude of the school's and town's problems in many ways are unrelated to Jeremiah's health. Even larger issues confront him, as a sports drug scandal exposes adult hypocrisy and duplicity, of a magnitude the boy has never had to fathom.
Support from his dad and making new friends keep him afloat even as it seems town morale is disintegrating. Jeremiah's resilience proves inspiring to others as they struggle to reconcile with sometimes harsh realities, including the death of a student. Jeremiah appears as smart and sensitive, but also mortal and hardly a superhero. The author thus reminds us of the importance of tenacity in overcoming limitations.

There are a few intertwined main ideas in Soar, a book by Joan Bauer. At first glance, one might think that this is a typical book about playing sports as an analogy for overcoming life's challenges. However, Jeremiah, the main character, cannot actually play the sport he loves, baseball. Instead, this book navigates real, complex issues of physical limitations, scandal, loss, adoption, and complicated relationships. While the book addresses tough issues in the life of a twelve-year-old, Bauer blends reality with laughter, warmth, and courage, as Jeremiah seeks to help coach his middle school baseball team. Jeremiah's friendship with Franny also highlights the ups and downs of adolescence while exposing the nature of family dynamics and the impact of fathers upon their children. Additionally, Bauer demonstrates how a community can be positively challenged by one determined and inspiring individual, regardless of that individual's age.