And now, researchers are encouraging parents and educators to do it more often, because there's new evidence that shows being " expressive" helps children learn.
The study by Colgate University researcher Spencer Kelly focused on children learning foreign languages. It found that children learn more easily and create stronger memories when their teachers use their hands to convey their meaning.
Gabriela Leon teaches an after-school Spanish club in Kirkland and she agrees that her hands can make a big difference helping her students to learn.
"We trust our eyes more than we trust our ears. It's such a big part of how we communicate," said Leon.
It's helpful news for teachers of foreign languages, but the Colgate findings have much broader implications, stretching all the way from early childhood learning to therapy for patients with brain trauma.
"Researchers are looking at hand gestures in autism, in downs syndrome.. different disorders that create language impairments. Patients with brain damage that affects speech, researchers are telling therapists to use their hands to help patients speak," said Kelly.
Kelly says researchers are just beginning to understand how " visual" we are as human learners. Researchers have even documented that people who are completely blind still use their hands as an expressive means of communication.
So, how can we put this research to use? Loosen up and use your hands while you're talking.
"It's more than just flapping your hands around. It has to be meaningful and natural," said Kelly.
In the classroom, Leon put the theory to work, first talking to her students about tying their shoes - without using her hands. No response. The beginner-level Spanish students had no idea what she was talking about.
Then she said the same thing, but used her hands. The students knew immediately that she was talking about tying her shoes.
And the research indicates that because she was using visual signals, next time Leon talks to her students about their "zapatos" (shoes), she may not need to use hand gestures, because a strong memory will already be there.
So, go ahead! Loosen up and use those hands. You may be helping someone learn without even trying.