Using research on employees' performance to study the effects of teachers on students' achievement 

[[abstract]]The study reported here used general ideas about employees' performance to develop and test a model of teachers' effects on students' achievement in mathematics using data from the longitudinal files of the National Education Longitudinal Study of 1988 (NELS:88). A general model of employees' performance suggests that the effects of teachers on students' achievement can be explained by three general classes of variables: teachers' ability, motivation, and work situation. This article discusses how these general classes of variables can be operationalized in the NELS:88 data set and presents estimates of models of the combined effects of these classes of variables on students' achievement. The analyses revealed that teachers' knowledge of subject matter and expectancy motivation have direct effects on students' achievement in mathematics and that the size of these effects depends on the average levels of ability of students in a school.[[note]]SSC