Start with 12 plastic cups. Use stacks of three, six and three cups to make and dismantle a series of pyramids until you are left again with the original stacks, the 3-6-3 combination.
Sound simple? Try doing it in 14 seconds.
The Speed Stackers Club of Roosevelt Elementary School in Willmar would be happy to demonstrate how it's done.
At this week's club meeting, advisers Larry Hastad and Kim Rosendahl had the Roosevelt gym ready for the group.
It's a colorful sport.
Tables were set up with decorative mats with built-in timers. Stacks of bright blue, yellow, green and purple cups dotted the mats. Some cups were decorated with flames.
After a snack and couple crazy games of tag, the 30 students in the club were ready to get down to some serious speed stacking after school on Monday.
Hastad set up a tournament with some of the students using the mats and timers. Rosendahl took some others to have them practice their stacking while doing one-handed pushups. Both of them are physical education instructors at Roosevelt.
Another group of students was making huge stacks with cups the size of small pails.
The cycle involves using the original 3-6-3 stacks and stacking and unstacking into a 6-6 formation, then into a 1-10-1 before returning to the 3-6-3.
The sport of speed stacking has been a popular one in physical education classes at the school, so about a year ago the instructors decided to try it out as an after-school activity, too.
An indication of the popularity was the number of students who were ordering their own speed stacks, Hastad said. Many of the club members bring their own stacks to the meeting. Some had regulation size cups, and others had miniatures.
Another indication of the popularity -- Hastad said he hears less complaining and has fewer students off task than in any other unit.
The speed stacking is something most students can do, even if they don't get to be very fast at it, Rosendahl said.
"It hits all abilities," she said. "A lot of times, you'll see athletes get frustrated with it."
Cup stacking works on a lot of skills, including dexterity of both hands, coordination and concentration. It requires some finesse along with the speed. The cups are light, and it's pretty easy to bump one and send it bouncing off out of reach, even off the table. With a timer running, it can be a costly error.
"That's what's hard, when they fall on the floor," said Callie Larson, 11, a fifth grader, as she watched a group in a tournament.
"You might think it's really easy, but it's pretty hard," added Josiah Swanson, 11, also a fifth grader.
Josiah and several other students said their favorite part of the stacking is the competition and trying to beat the clock.
"We have some students at about 14 seconds, which is really good," Rosendahl said.
Fifth-grader Scott Folz, 10, said he learns more all the time about how to move the stacks more efficiently. The best part of speed stacking is "the feeling of getting better and better at it," he said.
The club will finish its fall session on Monday. The winter session, open to grades 1-5, will run from 3:10 to 4:30 p.m. Mondays at the Roosevelt gym. The dates are Jan. 10, 17 and 31 and Feb. 7, 14 and 28. The cost is $15, and a simple snack will be provided.