For the study, the students were split into two groups. Half were shown a video of an instructor´s lecture where he did not use his hands. The other half of the students received the same information, but the instructor also used hand gestures.
Exactly why gestures help students learn better is still a mystery. The study authors said one possibility could be that gestures "clarify or provide conceptual information that is not readily apparent in the accompanying speech."
"Hand gestures can often times illustrate a concept that you can´t illustrate in speech," said co-author Kimberly Fenn, a psychology professor at Michigan State University.
Fenn suggests teachers and parents consider using their hands when trying to teach new concepts to kids. She said the key is using motions that convey meaning.
"Use your hands to not just reinforce what you´re saying but to illustrate what you´re saying," she said.
Previous studies have looked at the effectiveness of hand gestures, but this is the first study to look at how gestures play out in a classroom setting. A 2007 study found that teachers in Japan and Hong Kong are more likely to use rich and conceptual hand gestures than teachers in the U.S.
"Gesturing can be a very beneficial tool that is completely free and easily employed in classrooms," said Kimberly Fenn, study co-author and assistant professor of psychology at Michigan State University.
Half of the students were shown videos of an instructor teaching math problems using only speech. The others were shown videos of the instructor teaching the same problems using both speech and gestures. The problem involved mathematical equivalence (i.e., 4+5+7=__+7), which is known to be critical to later algebraic learning. In the speech-only videos, the instructor simply explains the problem. In the other videos, the instructor uses two hand gestures while speaking, using different hands to refer to the two sides of the equation. Students who learned from the gesture videos performed better on a test given immediately afterward than those who learned from the speech-only video.
Another test was given 24 hours later, and the gesture students actually showed improvement in their performance while the speech-only students did not. While previous research has shown the benefits of gestures in a one-on-one tutoring-style environment, the new study is the first to test the role of gestures in equivalence learning in a regular classroom.
The study also is the first to show that gestures can help students transfer learning to new contexts – such as transferring the knowledge learned in an addition-based equation to a multiplication-based equation.