Engineering, when integrated into K-12 education, may offer a number of potential student learning and future success benefits. In a 5-year study, four cohorts of elementary teachers of grades 2 to 4 in a single US school district were provided with teacher professional development with engineering education. Teachers were prepared to teach lessons to introduce and reinforce the terms engineering and technology, the work of an engineer, and the engineering design process and to engage students in an engineering design unit tied to grade-level specific science content. Teacher data (interviews) and student data (knowledge and identity development assessments, drawings, and interviews) were used to investigate the relationship between the teacher professional development and teachers' integration of engineering and students' learning and understanding of and interest in engineering. Access to data is restricted to researchers with legitimate research interests, though the research instruments are publicly available.