This study examined changes in the structural relationship among learner-centred classes perceived by Korean junior high school students, attitudes during class and academic achievement. A linear change model was identified as optimal, showing a steady increase over time for each parameter. The higher the initial value for learner-centred classes, the higher both the initial value and rate of change was for attitudes during class and academic achievement. The initial values for attitudes during class also had a significant effect on initial values of academic achievement, suggesting that attitudes are important in increasing academic achievement. The rate of change of both learner-centred classes and attitudes during class significantly influenced the rate of change of academic achievement.