MOUNT PLEASANT — Second-grader Kaleb Grieco can explain a few economic terms faster and better than some adults.

“The supply is the amount you have, and surplus means you have too much,” he said. “Scarcity means you don’t have enough to give to the whole class.”

Grieco understands what those words mean because he’s been studying them at Laurel Hill Primary as part of a 10-day, hands-on unit that culminated Tuesday.

The project involved all of the school’s more than 350 second-graders. It required them to apply for jobs and make crafts to sell to their peers.

To advertise their products, students designed and decorated signs, and they posted them around the school. One read: “Our Santa ornaments will make you Ho, Ho, Ho.”

Students earned “money” for their efforts, which included cleaning up, working cooperatively, making a quality product and showing up on time.

And on Tuesday, students had the chance to buy one another’s handmade goods.

This is the fifth year the school has hosted its “winter workshop,” and it’s become a favorite among some students and teachers. Students work on units throughout the year, but this one is easy to refer back to, because students have fun and remember it well, said second-grade teacher Amy Herndon.

“It lets them get their excitement out,” she said.

Second-grade teacher and project organizer Jennifer Cuneo got the idea for the initiative from a Columbia school where she previously taught. The lessons cover social studies, math and reading skills students are supposed to learn, and teachers go beyond grade-level topics to introduce concepts such as percentages.

“If you were trying to teach this with a textbook, I don’t know that they would understand it as well as they do now,” Cuneo said.

About half of the school’s second grade came together Tuesday in the school’s cafeteria for the shopping spree; the other half planned to do so today.

They could choose from goods such as “snowman soup” (hot chocolate), snowflake ornaments (Popsicle sticks, buttons and sequins), and reindeer clips made with dog treats.

The simulation created some real-life scenarios and lessons. One student asked for a refund after finding his ornament was defective (missing beads). Another second-grader sulked with his head in his hands after he spent all of his money on expensive items that later went on sale; he said he didn’t want to talk to the newspaper.

The item at the top of second-grader Faith Lou’s list was some snowman soup for herself. She planned to wrap up the rest of her purchases as presents for her dad, mom and brother.

She got a few items on sale, and she said she learned that if demand is high, the item will cost more.

Grieco knew the $10 Santa ornament he wanted would wipe out nearly half of his $21 in earnings, but it was his favorite. He bought it the first chance he got.

“I’m going to give it to my mom, and we could hang it on the Christmas tree,” he said.

Reach Diette Courrégé Casey at @Diette on Twitter or 937-5546.