Children were assigned to one of four groups based on their and their teacher's effortful control (EC).

Multilevel regression models examined mean differences among groups on kindergarten adjustment outcomes.

High-EC children with high-EC teachers tended to outperform other groups on reading and math assessments.

High-EC children with high-EC teachers tended to enjoy school more than other groups.

Low-EC children with high-EC teachers had the least close and most conflictual relationships with teachers.