We examined a novel formative assessment and instructional approach with 89 students in three electrical engineering classes in special computer-based discussion sections. The technique involved students individually solving circuit problems online, with their real-time responses observed by the instructor. While exploratory, survey and interview responses from 26 students suggest the technique offers important instructional and assessment advantages: Compared to typical discussion sessions, a large majority of respondents reported being more engaged, learning more, and interacting more with the instructor. Students reported the anonymous mode allowed them to ask "dumb" questions. The instructor was able to address student problems and questions immediately, and the amount of formative assessment information from the interaction far exceeded what was available in typical settings. (Contains 3 tables and 2 figures.)