Background: Science skills play a crucial role in fostering economic development and technological innovation, making the enhancement of science education a global priority. Despite the recognized importance of teacher practices in enhancing equitable and effective learning, much of the research on their impact on student outcomes has been conducted outside of the Nordic context and has predominantly focused on mathematics. Drawing upon teacher quality framework and the framework of three basic dimensions, the present study investigated the relations between teachers' cognitive activation practices (generic and subject-specific), teacher characteristics, classroom SES composition, and student achievement in biology, chemistry, and physics in the eighth grade. It also examined whether teachers' cognitive activation practices can mitigate the influence of student home educational resources on achievement. Methods: Using the Swedish TIMSS 2019 data, multilevel structural equation modelling analyses were employed. Specifically, we worked with a sample of 4029 eighth graders in 209 biology classes, 3735 eighth graders in 204 chemistry classes, and 3803 eighth graders in 214 physics classes in Sweden. Results: The results showed that biology achievement was positively related to teaching experience. Chemistry teachers' education level was negatively related to the first dimension of subject-specific cognitive activation (receptive scientific practices), while teaching experience was positively related to the second dimension of subject-specific cognitive activation (hands-on scientific practices). Furthermore, physics teachers' experience was positively related to the second dimension of subject-specific practices. Student achievement in biology, chemistry, and physics was positively related to classroom SES composition. Moreover, the results of the analyses showed that teachers' cognitive activation practices (generic and subject-specific) did not impact the relationship between student home educational resources and achievement in the three science subdomains in the eighth grade in Sweden. Conclusions: The findings call for further in-depth research regarding the mediating and moderating factors and mechanisms that can influence the relationship between SES and student science achievement in biology, chemistry, and physics.