OVERESTIMATING OR OVERLOOKING? TEACHERS’ BIASED ASSESSMENT ON DIFFERENTIATED READING GROUPS

Abstract

In heterogeneous classrooms, teachers frequently make diagnostic decisions about how to differentiate instruction and allocate learning materials. However, research suggests that adaptive teaching decisions should be guided by data -based decision -making ra ther than social comparisons or personal traits. This study examines how N = 350 primary school students (grades 2 and 3) were assigned to differentiated reading materials – either intuitively by teachers or based on standardized reading assessments. Group ing patterns, decision factors, and biases were analyzed. Teachers matched the assessments in 52 % of cases, underestimated 34 %, and overestimated 14 %. They also tended to create comparable sized groups (24 % – 41 %), whereas standardized assessments identified 51 % of students as high-, 44 % moderate-and 5 % low -performing. Providing teachers with standardized results led to minor adjustments – 82 % of students remained in the intuitively assigned group. Multinomial logistic regressions indicated that i ntuitive group assignments and discrepancies between intuitive and standardized assignments were associated with selected student -related characteristics, including individual performance relative to the class mean, documented migration background, and doc umented behavioral or work -related issues. The findings highlight challenges in implementing data -based decision -making in everyday classroom practice and underline the importance of strengthening the systematic use of assessment data in teacher education.