Parents on the verge of pulling out their hair while trying to get misbehaving pre-schoolers to behave can rejoice — a new study is shedding light on a technique that could help.

According to research out of Brock University, it's a relatively simple approach; just get your kids to say out loud what it is they're promising to do. Think, "I promise not to steal any cookies from the jar," or "I promise not to repaint the walls of my room with fluorescent markers."

"It definitely improves the likelihood of them adhering to what you're asking them to do," said Angela Evans, an associate professor in the university's department of psychology who led the study of 99 children under 5.

'It's an easy little tool, and I'd really like for parents to have it.' - Angela Evans, study author

Here's how it worked:

Researchers sat down preschoolers while a stuffed elephant was placed behind them on a table. They were asked not to turn around and look at the toy when the experimenter was out of the room, and then hidden cameras in the room captured whether or not they did.

Naturally, kids being kids, 80 per cent of them cheated and snuck a look, even after agreeing not to.

But after the kids were asked to make a specific commitment out loud to not look, (as in, "I promise not to look at the toy,") the cheating dropped to 58 per cent. Researchers say it also took a lot longer for the kids who promised out loud to sneak a look at the toy.

"It becomes their own personal commitment … when you say something our loud, it becomes a part of yourself and your commitment," Evans said.

"It's not going to be a magic wand, but for situations that you really want to make sure they've processed something, it increases the likelihood."

Angela Evans

Angela Evans (left) is an associate professor at Brock University’s department of psychology. (Brock University)

Other studies have shown that children over the age of five were more likely to be honest if they just agreed with a promise to tell the truth, a university press release reads. Those promises were shown to be ineffective in children under five, though.

That's where Evans' research comes in. She says it was her interest in how children are socialized to become honest that steered the direction of her research.

It also helps that she has a two-year-old and a four-year-old of her own at home. "I've started using it with my own daughter," she laughed.

"It's an easy little tool, and I'd really like for parents to have it."

adam.carter@cbc.ca