Research has shown that academic achievement is positively correlated with improved employment opportunities, social skills, well-being, standard of living, and overall quality of life. One variable that has been shown to significantly influence academic achievement are the seats that are used by students in the classroom. The aim of the current study was to investigate the impact that Bodyfurn chairs had on academic achievement by evaluating the effect that they had on-task and disruptive behaviour of students compared to the regular classroom chairs. It was hypothesized that Bodyfurn chairs would increase the on-task behaviour and decrease disruptive behaviours of students. The study included three separate groups of five primary school students and implemented a multiple baseline design. All three groups used the regular classroom chairs during the baseline phase and Bodyfurn chairs were introduced in a staggered fashion once stable baselines were established. The results showed that the introduction of Bodyfurn chairs resulted in immediate and noticeable increases in on-task behaviour for two of the groups, with on-task behaviour increasing by 27.4% and 15.7% relative to the regular classroom chairs, while a ceiling effect prevented any noticeable experimental effect from occurring in the third group. The results also showed marked decreases in disruptive behaviour across all three groups when Bodyfurn chairs were used with occurrences of disruptive behaviour decreasing by 49.1%, 47.8%, and 59.5% compared to the regular classroom chairs. The findings of this study suggest that Bodyfurn chairs could improve academic achievement of students.