In 1-3 sentences, write a brief summary of the book.

Published in 2003, Jerry Spinelli's Loser is a children's novel about a boy who struggles to fit in with his peers due to his clumsiness, poor grades, and lack of self-awareness. Nicknamed "Loser" after failing to win a team race, Donald Zinkoff becomes the target for teasing and taunting. Despite adversity, Zinkoff remains enthusiastic about school and life. The book follows Zinkoff from first grade to middle school, detailing an inner life that is upbeat and imaginative despite the bullying, ridicule, and invisibility he faces.