Trends in between-school and between-class variation in student achievement in the Nordic countries based on IEA assessments from 2011 to 2023

This study explores the development of between-school and between-class variation in student achievement in Nordic basic education between 2011-2023, drawing on international large-scale assessments conducted by the IEA: TIMSS and PIRLS. Recent demographic and geographical developments, for example in Finland, such as increasing residential segregation, have contributed to growing disparities in student backgrounds across schools, reflected in learning outcomes from an early stage.<br/>We address the following research questions: (1) How has between-school and between-class variation evolved in Nordic countries excluding Iceland? (2) To what extent can differences in achievement be explained by structural factors at the school and class level compared to individual socioeconomic status? (3) How have these associations changed between 2011 and 2023?<br/>Our analytical framework is based on the Douglas Fir Group’s (2016) transdisciplinary model of language learning, which considers how learning is shaped by individual, social, and structural factors. Using multilevel modeling and decomposition analysis, we examine how much of the variance in student achievement is attributable to school-, class-, and individual-level characteristics. Control variables include socioeconomic status (SES), absenteeism, and language spoken at home. Findings show increasing variation in Finland and Sweden, particularly in reading, while Norway and Denmark show more stable trends.