The experiment worked for Bethany Linville.

Holding up her plastic Easter egg Tuesday morning, she was beaming.

“The first egg I found was a purple one, but I wanted a green one, so I went searching for a green one,” the Kansas University sophomore from Wichita said.

She found one. It matched her green plastic sunglasses frames and green backpack straps, too.

“I’m ecstatic,” she said.

And that was the point.

The impromptu Tuesday morning Easter egg hunt was the brainchild of a dozen undergraduate psychology students, who hid 500 eggs across campus in an effort to see how happy they made people.

It’s all part of Sarah Pressman’s positive psychology class.

“Most of what psychology studies is depression and stress and the bad stuff,” said Pressman, an assistant professor of psychology. “The whole positive psychology research field is really focused on trying to correct that.”

People who report being happy can live up to eight years longer than those who don’t, she said.

Happiness comes with other benefits, too.

“It reduces your stress hormones, it improves your immune system function, it can decrease your likelihood of developing heart disease, and if you do have a heart attack, if you’re more optimistic, you get out of the hospital faster,” she said.

With that in mind, students in Pressman’s class were tasked to come up with projects designed to make Lawrence a happier place.

This Easter egg project is part of that. Students who nabbed an egg found two pieces of candy and a slip of paper directing them to keep one piece and give the second to someone else — then to take an online survey to provide feedback for the undergraduate researchers to ensure that students learn research methods, too.

Stephanie Lanning, a senior from Shawnee, was one of the group members. She enjoyed seeing the fruits of the group’s work.

“Spreading happiness is just as important as being happy,” she said, recalling a point from class, to the delight of her professor, who was standing nearby. “Giving is just as important as receiving.”

Look for other projects soon. One group plans to have a giant recess, another has a surprise in store for an entire floor on campus, and a third plans to have a big public mural where people can write messages.

Does Pressman ever worry about all this seeming a little, well, hokey?

“Constantly,” she said. “The whole field, there’s always some cynicism out there, like who cares about happiness?”

But that’s why she does scientific research on it — to show that happiness matters on a physiological level.

For students like Cody Wilson, a senior from Dallas, it’s a welcome change from other classes.

“Usually, when I leave a psychology class, I think, God, there’s so much wrong with me,” he said. “It’s nice to start to see the good part of yourself.”