In the book "Schoolhouse Mystery" by Gertrude Chandler Warner, a pivotal character is described with a striking appearance. The man features blond hair, which stands out, and his warm smile, which reveals all of his teeth, adds to his friendly demeanor. This description not only highlights his physical traits but also hints at his personality, making him an engaging character in the story.

The character's cheerful countenance suggests an openness, inviting a sense of trust and curiosity from those around him. His blond hair and bright smile might serve as symbols of clarity and honesty, elements that are crucial in a mystery narrative. This blend of charm and intrigue is essential in advancing the plot and engaging readers in the unfolding events of the mystery.