In view of student heterogeneity, teachers need to adjust their teaching to the diverse learning needs of the students and thus require adaptive teaching competency. While adaptive teaching competency is often seen as a prerequisite of quality of instruction, the ways in which adaptive teaching competency is conceptualized and measured are diverse. This paper proposes a model of adaptive teaching competency and describes a multi-method approach, including text vignettes, a standardized video test and student questionnaires. The study explores whether students who are taught by a teacher achieving higher scores in measurements of adaptive teaching competency rate classroom processes more positively, as well as whether the measured adaptive teaching competency has a positive effect on student learning outcome and furthermore how such an effect can be explained. The sample consists of 49 primary and secondary teachers and their classes, including 898 students. Student achievement was measured with pre- and post-tests on a set science topic which teachers were asked to teach in eight lessons according to specified curricular goals. The results indicate a statistically significant positive effect of adaptive teaching competency on students’ achievement. The results of a Multilevel Structural Equation Model (MSEM) analysis lead to the conclusion that adaptive teaching competency is not affecting learning outcomes directly but mediated through a high quality of classroom processes.

Keywords
Adaptive teaching competency (ATC), Teacher effectiveness, Teaching quality, Academic outcome, Diverse learning needs