Examining socioeconomic status as a moderator of science motivation and achievement

This study aims to examine thoroughly the moderating role of socioeconomic status (SES) at both the student and school levels in the relationship between 8th-grade students' science achievement and their intrinsic motivation, instrumental motivation, and science self-concept, using data from TIMSS 2019 and TIMSS 2023. The study sample consists of 4,077 students from 181 schools who participated in TIMSS 2019 and 4,925 students from 141 schools who participated in TIMSS 2023 in Turkey. The conceptual model of the study is based on Self-Determination Theory (SDT). The results of the hierarchical linear modeling (HLM) analysis indicate that 35.5% of the total variance in 2019 and 32.2% in 2023 can be attributed to differences between schools. Additionally, a strong relationship was found between students' SES levels and their science achievement in both years. 71.65% and 64.86% of the between-school variance was explained solely by school-level SES in 2019 and 2023, respectively. At the student level, SES explained 7.35% of the variance in 2019 and 6.68% in 2023. When examining motivational variables, science self-concept was found as the strongest predictor of science achievement in both years. In 2019, 8.4% of the within-school variance was explained by intrinsic motivation, 2.5% by instrumental motivation, and 23.5% by science self-concept. According to the 2023 data, 2.1% of the within-school variance was explained by intrinsic motivation, 0.3% by instrumental motivation, and 15.6% by science self-concept. Furthermore, only in 2019 was the interaction between school-level mean SES and science self-concept found to be statistically significant. This finding suggests that SES at the school level plays a moderating role in the relationship between science self-concept and science achievement.