The Draw an Engineer Test (DAET) is a common measure of students' perceptions of engineers. The coding systems currently used for K-12 research are general rubrics or checklists to capture the images presented in the drawing, which leave out some of the richness of students' perceptions, currently only captured with an accompanying student interview. The purpose of this study is to build a reliable coding system, which first establishes an inventory of pictorial elements irrespective of their potential relationship with engineering and second captures aspects of students' engineering perceptions inductively (from the ground up) while at the same time incorporating categories from previous research. The coding system will be used to help researchers understand how young students' perceptions of engineering, engineers, and the work of engineers evolve and are impacted by interventions. The long-term goal of this project is to create a stand-alone measure that can be broadly applied to diverse populations, and to create a large multi-institution student database, with both K-12 and university populations represented. This database would provide a rich dataset for better understanding common misconceptions about engineering and thus enabling the development of methods to address them.