Teacher-student interactions are crucial in understanding the role of a supportive climate in instructional practices. The present study investigates the perceptions of 15-year-old Nordic students regarding four aspects of their science class: teacher support, fairness, feedback, and class discipline. Multilevel modelling analysis is used to examine the extent to which a perceived supportive climate can explain variation in the Nordic students' science achievements. Overall, the main findings based on The Programme for International Student Assessment (PISA) 2015 data from Denmark, Finland, Iceland, Norway, and Sweden indicate that at the student level, perceived feedback from teachers and students perceiving their teachers as fair explains significant variations in science achievement. The study provides practical and theoretical implications about the importance of strong teacher-student relationships in comprehending the concept of a supportive climate.