Among a group of 122 elementary school kids taught a weeklong curriculum on concepts around giving, gratitude grew, according to a study due to be published in 2014 in School Psychology Review. The heightened thankfulness translated into action: 44% of the kids in the curriculum opted to write thank-you notes when given the choice following a PTA presentation. In the control group, 25% wrote notes.

“The old adage that virtues are caught, not taught, applies here,” says University of California, Davis psychology professor Robert Emmons. Parents need to model this behavior to build their children’s gratitude muscle. “It’s not what parents want to hear, but you cannot give your kids something that you yourselves do not have,” Dr. Emmons says.

This may seems obvious, but it eludes many parents, Dr. Watkins says. “I think the most important thing for us adults to realize is we’re not very grateful either,” he says.

The mere act of giving thanks has tangible benefits, research suggests. A 2008 study of 221 kids published in the Journal of School Psychology analyzed sixth- and seventh-graders assigned to list five things they were grateful for every day for two weeks. It found they had a better outlook on school and greater life satisfaction three weeks later, compared with kids assigned to list five hassles.