We're all familiar with Hollywood's vision of masterful teaching: jumping up on the desk and regaling your students with engaging and impassioned monologues. We, the audience, are rapt and staring at the teacher - but what are the kids doing? For the most part, sitting and listening. Which is fine, some of the time, and particularly for certain independent learners. But there are a couple of problems with this picture. First, the Hollywood teacher isn't getting very much participation - kids are mostly passively receiving information. And second, kids aren't exactly breaking a sweat. Their teacher isn't asking them to do anything intellectually rigorous. This mini makes the case for attending to "participation" and "thinking" ratio to promote classroom learning. (But don't worry - there's still room for jumping on desks and sounding your barbaric teaching yawp.)