Despite the recent technical and theoretical advances in the investigation of children's social relations, the inherent complexity of these methods may prevent their easy integration into the classroom. A simple and effective tool can be valuable for teachers who wish to investigate students' social realities in the classroom. Therefore, the…

Task persistence, measured by a composite score of independent teacher, tester and observer reports, was examined using behavioral genetic analysis. Participants included 92 monozygotic and 137 same-sex dizygotic twin pairs in Kindergarten or 1st grade (4.3 to 7.9 years old). Task persistence was widely distributed, higher among older children,…