Lectures at home, homework in class

On a Thursday morning this November, ChemE juniors filed into their introductory thermodynamics class. But instead of settling into desks all facing forward, they found their seats at small tables with 4 or 5 classmates; took out notebooks, calculators, and tablet computers; and got to work on their weekly problem set. At the start of the session, professor Stu Adler drew one diagram on the board, told the students that it’d likely be helpful in that day’s work, then turned off his microphone.

Welcome to a “flipped” class. Adler is in his third year of teaching thermo this way, and it works like this: Students watch Adler’s lectures and demonstrations on video outside of class. Then they spend their class time working on practice problems that in a traditional classroom would be assigned as homework. During class, Adler visits the table groups, reinforcing key concepts and helping students pick up those they may have missed. In the flipped format, all class sessions — not just office hours or recitations — offer opportunities for individualized instruction. It can save students the time and frustration of getting stuck on homework because they missed something in a lecture.

TA Jon Witt offers individualized instruction to students in thermo class

The flipped classroom represents an extreme form of active learning, an educational approach the department is increasingly adding to its curriculum. Adler is a strong proponent, and has data from his flipped classes showing its promise. In short, he’s found that more students are mastering more of the concepts. Instead of class grades in a bell-curve distribution, they stack up at the high end. Adler attributes this to the level of descriptive feedback, as opposed to grades, that he’s able to provide in this format. TA Brian Gerwe sees it happening, too, finding there to be “a lot more teachable moments” than in a traditional setting.

The success doesn’t come easy. Flipping a class comes with a huge upfront cost, says Adler. A lot of time and thought goes into preparing lecture videos, especially since they don’t allow for the immediate feedback that’s possible in a live lecture setting. “I try to compensate [for the lack of Q&A] by explaining concepts in lots of different ways,” he says, and sometimes that’s through lab demonstrations. “They can’t get that from me standing at a blackboard.”

Other ChemE instructors are trying this approach, too. David Beck is using it in the data science curriculum. Chad Curtis (Ph.D. ’19, now a lecturer) TA’ed one of Beck’s courses, and having been inspired, is planning to flip the Chemical Engineering Computer Skills class. For this type of course, Curtis says, he’s seen firsthand the value in freeing up lecture time for discussion and individualized help in the computer lab.

It’s often quipped that ChemE’s don’t let ChemE’s do homework alone. In a flipped classroom, they’re always in good company.