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Figure 4. George Mason University’s Active Learning with Technol- ogy classroom is designed to support collaborative, student-centered learning. The whiteboards on the walls and projection to dedicated flat-screen displays encourages student interactions. Photo from Cre- ative Services/George Mason University, with permission.
bers of each group to submit their collaborative solutions, then grading one randomly chosen paper from each group (Johnson et al., 1998).
“Muddy point” cards offer an opportunity for students to provide feedback to instructors. We give students index cards at the end of class and ask them to write down some- thing that is still confusing to them about the day’s material. The cards are anonymous and provide immediate feedback to the instructor about the students’ understanding. We can address the contents of the cards either by a short email later that day or by recording a video with some additional ex- amples or instruction (see next section).
The integration of these active-learning techniques provides students with feedback on many time scales, shown in Fig- ure 5. Starting from the introduction of a topic in class (t = 0), students receive feedback on timescales of minutes, hours, days, weeks, and months. Frequent feedback and re- call leads to stronger memories, resulting in better student mastery of material (Brown et al., 2014, pp. 33-39). Instruc- tors are also receiving feedback about the students’ under- standing on all of these timescales, allowing them to react and address misconceptions early in the learning process before they become entrenched (Brown et al., 2014, pp. 44). In contrast, a traditional lecture course provides feedback to students only on the longer timescales of weeks and months.
Video Killed the Lecture Star
The largest change to our implementation of active learn- ing in the decade since publishing Buck and Wage (2005) is the incorporation of YouTube video lectures to supplement the classroom instruction. Ideally, these video lectures run 10-15 minutes in length. Our video lectures do not just du-
Figure 5. Active-learning classes (blue) provide feedback to students about their understanding on many short timescales in addition to the traditional homework assignments and grades. Traditional lec- ture classes (red) only provide feedback on the longer timescales of weeks and months, resulting in less effective memory formation.
plicate classroom lectures but instead present examples or additional exposition to address a specific student miscon- ception identified while grading in-class problems or home- work or while reading muddy point cards. Some recordings cover examples we set aside from our old lecture notes to free time for in-class problem sessions. “More examples please” is a perennial refrain on student evaluations, and the videos offer one way to address this request. Finally, some recorded lectures cover secondary material that students should be able to digest once they master the major points in class. For example, after teaching the fundamentals of the Z- transform during the short in-class lecture, we relegate the discussion of various transform properties to video lectures for later viewing.
Our videos opt for a simple presentation. Inspired by the popular Khan Academy videos (www.khanacademy.org), we show writing on screen using a whiteboard program along with synchronous audio narration. This format emulates the experience of an instructor and student sitting side by side with a piece of paper during office hours. We believe this approach encourages student engagement. Moreover, we believe that other common presentation modes for instruc- tional videos such as lecture hall recordings, narrated slides, or talking head videos with slides implicitly put students in the mind frame of more passive experiences, such as attend- ing a large lecture or watching TV. Guo et al.’s (2014) study of MOOC videos supports our intuition on presentation for- mat. Guo et al. found that short Khan-style videos and an in- formal style improved student engagement in online videos over narrated slides or lecture hall recordings.
Contrary to popular belief, producing instructional vid- eos need not demand the time and resources required to Summer 2016 | Acoustics Today | 17