Martha Kaply is a shy bookworm who got detention for objecting to participating in physical education. While in Jumanji, Spencer tells her that he likes her and she admits that she also has feelings for him.
Martha is a bright student like Spencer, but had no interest in physical activities or boys. She also dislikes like having tattoos on her body, because her mother would kill her if she got one.
As the film progresses, Spencer began to have feelings for her and she has feelings for him. By film's end, it is possible that they became a couple.