In this paper we present results from administering the Determining and Interpreting Resistive Electric Circuit Concepts Test (DIRECT) concept inventory to first-year honors engineering students (n?150). This study was coordinated around a one-week module on electrical circuit theory, with the concept inventory administered immediately before and after the module. Students were also given an open-ended questionnaire during the pre-test, and a survey to evaluate the instructional module with the post-test. We discuss details of the instructional module and present several findings from our analysis of the survey data. We find that while a majority of the students had completed Advanced Placement (AP) physics and/or electronics courses and were currently enrolled in college-level physics courses, they still had many difficulties solving basic problems involving resistive circuits and did not show significant improvements after completing the instructional module. Our findings highlight many of the persistent difficulties faced by students in this conceptual domain. Factors such as prior educational experiences and intended major (i.e., ECE vs. non-ECE) were shown to predict student performance on the concept inventory. We conclude the paper by first describing how this study has informed a new stage of research involving a more in-depth qualitative study of misconceptions in this domain, including across student levels (i.e., first-year to junior/senior). We also discuss how a number of insights from this study can help instructors and curriculum developers assess and improve conceptual understanding in the context of their own courses.