Three teaching methods were compared in this study, namely a Cognitive Conflict Management Module (CCM) that is infused into Cognitive Acceleration through Science Education (CASE), (Module A) CASE without CCM (Module B) and a conventional teaching method. This study employed a pre- and post-test quasi-experimental design using non-equivalent control groups. The design involved 130 participants from Form 2 (Grade 7) in a Malaysian secondary school. The cognitive level of all participants was classified as non-formal operational on the pre-test and were allocated to one of the four intact groups: experimental group 1, EP1 experienced Module A, experimental group, and EP2 experienced Module B, while the others were divided between two control groups. The impact of the three teaching methods on the level of cognitive development and science achievement were observed after a 20-week intervention. Data were analysed using multivariate analysis of variance/multivariate analysis of covariance, analysis of covariance and a paired-samples t test. It is hoped that this study can contribute to knowledge in the field of cognitive intervention and cognitive conflict strategy. The findings show that a high dose of cognitive intervention in CASE activities within a short period has an effect on the levels of students' cognitive development, standard science achievement and constructive cognitive conflict.