As a class, circuits has a much heavier workload than the listed 3 credits. In addition to zybook activities that can take 1-2 hours (with the exception of the last one taking 5+), there is a weekly homework that takes 1-2 hours and a weekly lab which outside of the lab time can take an additional 2-4 hours depending on if the lab requires a formal report. As a class, some of the concepts can be confusing, and at times more so on the homework. The TA's are very helpful though and I highly recommend office hours. As a professor, Barnes creates slideshows for all of the lectures that are very detailed and helpful. My only complaint is that I feel that Professor Barnes sort of skims the slideshows. Although the slideshows are useful, I don't feel that Barnes always explains more difficult concepts quite in depth enough.