PROBLEM: Math is terrible. And terrifying. It's so bad that just thinking about having to do math is enough to activate pain receptors in some people's brains. And few things can make it less terrifying. Muppets singing about math helps, sometimes, unless you're my friend who's afraid of muppets. My one experience with a math tutor didn't help, because I was legitimately creeped out by how excited he became at the prospect of solving equations.

METHODOLOGY: Researchers at Michigan State went out to local public schools and showed educational videos to 184 elementary school-aged children. In the videos, an instructor introduced them to the concept of mathematical equivalence (7 + 2 + 9 = 7 + __), in which one side of the equation always has to equal the other side. The problems were displayed next to her on the screen; in half of the videos, she used hand gestures, sweeping her left hand beneath the left side of the equation when she said "one side" and her right hand beneath the right side of the equation when she said "the other side." In the other half, she just talked at them.

The students were tested on their ability to solve such equations both immediately after watching the video and 24 hours later. They were also given a test that demonstrated the same principles, but in new configurations.

RESULTS: As anticipated from the results of similar studies, the students who learned how to solve the problems with hand gestures performed better than the others on the immediate test. But then a day later, those same students -- who were already ahead -- showed even more improvement. The students who weren't shown gestures had no change in their ability. Thus, the authors conclude, "gesture affects initial learning, and additionally affects how learning is consolidated over time."

There were limits to how much they learned, however: When tested on their understanding of the general concept of equivalency (for example, could they solve problems that looked the same but used multiplication instead of addition) the gesture students failed to perform significantly better than the others.

IMPLICATIONS: I still feel like an enthusiastically gesticulating teacher would make me even more uncomfortable than solving for x already does. The authors aren't sure why it works, either, but they think something relatively profound might be at work. They propose that gestures actually change something about what the children are learning, perhaps by clarifying or providing additional information about what the teacher is saying, or even by engaging their motor memory. Gestures are special, they write, because they're able to "simultaneously express abstract relations while linking these relations to specific entities available in the environment." Or maybe they just scare the kids into paying attention.

"Consolidation and Transfer of Learning After Observing Hand Gesture" will be published in Child Development.