Engineering, with its focus on design and problem-solving, is used in K-12 education to promote learning in STEM (science, technology, engineering, and mathematics). In this special issue, we bring together seven research papers that have examined critical questions in engineering education. These papers collectively examine recent research in K-12 education and address three broad topics: different models for integrating engineering into K-12 curricula, different learning outcomes associated with alternative models of integration and implementation, and ways K-12 students engage in epistemic practices of engineering while learning STEM concepts. Future research needs to address how engineering should be implemented in schools, what and how learning outcomes must be assessed, and how engineering should be taught. Further research in K-12 curriculum, student learning, and teacher education is necessary, as are applications of contemporary research methods to study teaching and learning of engineering concepts and practices in elementary and secondary schools.