Interesting implications for the flipped classroom.  If students think they already understand something, they’ll tune out of a video lecture.

Students watched a science video they frequently described as “clear,” but in a post-test it turns out the video had actually confirmed their incorrect assumptions.

When students watched a second video that first presented and then corrected common misconceptions, they never described that video as “clear,” and in fact they often described it as “confusing” — but they doubled their score on an objective post-test.

Khan Academy and the Effectiveness of Science Videos – YouTube.

So, when students were happily clinging to their unexamined misconceptions, they described as “clear” the video they completely ignored.

When students were forced to reexamine their understanding, they called the material “confusing,” and they reported putting extra mental effort into the material; but in this case, the post-test shows measurable learning.