Recent global educational initiatives and reforms have focused on increasing the number of students pursuing STEM subjects, and ensuring students are well-prepared, and suitably qualified to engage in STEM careers. This paper examines the contributions of the four disciplines--Science, Technology, Engineering and Mathematics--to the field of STEM education, and discusses STEM literacy; factors influencing students' engagement in STEM education; effective pedagogical practices, and their influence on student learning and achievement in STEM; and the role of the teacher in STEM education. Through a critical review of 237 studies, three key factors were identified: (1) the importance of focusing on the junior secondary phase of schooling to maintain student interest and motivation to engage in STEM, (2) the implementation of effective pedagogical practices to increase student interest and motivation, develop 21st century competencies, and improve student achievement, and (3) the development of high-quality teachers to positively affect students' attitudes and motivation towards STEM.