One response to a pedagogical shift towards student-centred and active learning approaches to promote student learning in STEM is the flipped classroom. However, there has been inconsistency in the design and implementation of the flipped classroom and its impact on student learning. This review systematically analysed 30 empirical studies on flipped classrooms in formal, K-16 science and maths classrooms to understand theoretical underpinnings leading to different approaches to flipped classrooms and the impact of flipped classrooms on student learning in science and maths classrooms. The selected studies were qualitatively analysed, and the results showed that: (1) there is more published literature on the flipped classroom identified in post-secondary science and mathematics classrooms, (2) the design of the flipped classroom is rarely grounded in theoretical frameworks especially in science classrooms, and (3) the flipped classroom has an overall positive effect on students' science and maths learning. This study highlights the importance of using explicit theoretical frameworks aligned with contemporary learning theories to guide the design, implementation, and evaluation of the flipped classroom. Additionally, there is a need for future research to utilise design-based methodologies to maximise the positive impact of the flipped classroom on student learning.