Late childhood spans from age 6 until sexual maturity. This stage is marked by profound changes that affect social and personal adjustment as children enter first grade. Physical changes occur and influence attitudes, values, and behavior. Boys and girls mature sexually at varying ages during this period. Late childhood is characterized by names like the troublesome age, sloppy age, and quarrelsome age from parents' perspectives and the elementary school age and critical period of achievement from educators' views. Psychologists may call it the gang age, age of conformity, creative age, or play age. Key developmental tasks include physical development and mastering elementary school work.