Background: The Next Generation Science Standards accentuate engineering design along with scientific inquiry, emphasizing the relationship between scientific investigations and engineering design in solving problems and devising new ideas and technologies. The goal is for students to realize the importance of science and engineering in innovation and in solving many of today's challenges. The Next Generation Science Standards contends that a working knowledge and practicality of engineering design prepares students for embracing the challenges of the future. To support students in developing these capabilities, teachers are tasked with the responsibility of facilitating science instruction that integrates science and engineering practices. This is a challenge since a majority of them have little to no understanding of engineering applications. Results: An interdisciplinary team, consisting of science education and mechanical engineering faculty and doctoral students from each discipline, and science, mathematics, and career and technical curriculum supervisors, collaborated with middle school science, mathematics, and career and technical education teachers to develop a framework for integrating engineering practices into their curricula. The exploratory nature of the project, and instructional outcomes with their students, supported teachers in developing an understanding and value for science and engineering practices. As a result, they were motivated to critique and revise their practices, aiming to develop and implement instruction that they perceived as beneficial to their students. Conclusion: With the surge in emphasis on preparing K-12 students for the STEM workforce, initiatives devoted to exposing teachers and students to STEM applications have also increased. The findings from this study could be useful for informing these initiatives, since they reveal the learning experiences of the teachers while processing instructional strategies for integrating science and engineering practices into their curriculum. The findings highlight factors that motivated these teachers to reform their instructional practices, as well as their deliberations while endeavoring to assimilate the strategies into their curricular activities.