Greta J. Warner, Johanna Nele Lensing, Doris Fay

• Although the effects of personal initiative (PI) on adults' performance and other favorable outcomes are well documented, research has only recently begun to study PI in childhood. This study aimed at examining the development of PI, its predictors, and its developmental effects from childhood to early adolescence. A total of 1,593 German children participated in a longitudinal study starting at Grades 2 to 4, with a second measurement wave two years later. Latent change score analyses revealed that 1) children differed significantly in their change scores of PI, that 2) executive functions and positive parenting predicted change scores in PI, and that 3) high initial levels and change scores in PI reduced the development of internalizing and externalizing problems and supported the development of prosocial behavior and academic competencies. These findings endorse the plasticity of PI and shed light on the active part of children in promoting their own development.