Teachers feel that by integrating a little sprinkle of technology and engineering mixed in mathematics and science is enough to integrate STEM across all four disciplines. This shows how one of the biggest educational challenges for K – 12 STEM education is that few general guidelines or models exist for teachers to follow regarding how to teach using STEM integration approaches in their classroom. This also goes to show how the most common conception of STEM education might be the notion of integration – meaning that STEM is the purposeful integrations of the various disciplines as used in solving real – word problems. Despite the benefits of integrated curricula seem clear, there are barriers that must be negotiated when teachers choose to implement integrated STEM curricula. Therefore, the focus of this literature review will also be on quantitative studies that provide information on teachers continuously using a traditional instruction contradicting the definition of integrated STEM education. To implement effective integrated STEM education, attention has been paid to teachers' using constructivist teaching strategies to implement integrated STEM education that can help students gain interest in STEM subjects.