The Next Generation Science Standards (NGSS) Framework of 2013 includes engineering practices as a part of the eight Science and Engineering Practices, and as individual Performance Expectations. Several problems exist around the teaching of Engineering Science in the United States. Teachers are entering the teaching profession with a lack of knowledge, experience, and pedagogy related to understanding and teaching engineering. Additional problems are a lack of funding for curricular materials, supplies, as well as a lack of continual professional development. The purpose of this phenomenology-based study was to (a) document the lived experiences of 21 criteria-selected science teachers implementing NGSS Engineering Practices, and (b) to explore the contextual meaning of these teachers through the situational knowledge gained through targeted professional development. The professional development was provided by a California Math and Science Partnership (CaMSP) grant. Four key themes emerged from the data analysis: (a) Limited Understanding of the Engineering Design Process (b) Challenges of Engineering Implementation in the Classroom (c) Support for Engineering Implementation, and (d) Developing Engineering Habits of Mind. This study highlights uncovered barriers to the implementation of engineering such as; a lack of time, materials, teacher preparation, curricular materials and funding. Additional findings indicate the participants all believed engineering is necessary to help students succeed in future careers and realized the value in teaching and learning engineering. The engineering-focused professional development provided by the CaMSP increased knowledge of the engineering design process and how to implement this process into core science subjects.