Engineering education can be a wonderful mechanism for students to apply mathematics and science in authentic real world settings; however, less than half of U.S. states have engineering requirements in their mathematics and science standards. The many positives of engineering education can be used to help teachers see the benefits of integrating engineering. This article explores engineering activities written by elementary teachers both before and after a year-long professional development focused on STEM education. The teachers did not have any required engineering state standards, but increased their knowledge about engineering education, and saw the benefit of this approach. The activities were evaluated based on a framework for quality K-12 engineering education. The teachers improved in their inclusion of the engineering design process, and in their understanding of design constraints. The teachers' activities could still be improved though with respect to incorporating redesign and the explicit integration of mathematics and science.