What was Arnold Gessell's contribution to school psychology in 1915?

Arnold Gesell made significant contributions to the field of child development, particularly through his focus on measuring children's developmental milestones. In 1915, he conducted systematic observations and developed age-related norms that were influential in understanding the growth and development of children. By employing rigorous methods to track various developmental aspects such as motor skills, language acquisition, and social behaviors, Gesell laid the groundwork for developmental psychology and its application to education.

His work established the importance of understanding child development in educational settings and provided a scientific basis for assessing children's readiness for school. These insights helped school psychologists identify developmental delays or atypical trajectories, allowing for appropriate interventions and support for students. This focus on development was crucial in educating teachers and parents about the varied rates at which children grow and learn, aligning with the evolving needs within the educational system.