This study investigated the level of understanding among student teachers in differentiating lepidopterans. It adopted a constructive approach to promoting conceptual change in students on the issue of animal classification by generating cognitive conflict. Most of the students used inaccurate morphological traits for identification, such as wing colouration and pattern, resulting in a low mean score of 49.7% in the pre-test. After the constructive learning intervention, they achieved a score of 79.7% in the post-test, revealing the effectiveness of the approach. Gender differences in performance were not correlated with negative attitudes towards the insects. (Contains 3 figures and 2 tables.)