If the ground starts shaking...

An imaginative youngster can crawl under a table and declare it a cave or a fort. On Thursday, that space was an earthquake protection zone.

As part of the Great Arizona ShakeOut, an earthquake preparedness drill held around the state, people of all ages remembered to take cover if the ground started to move. Yuma County was especially keen to participate in the drill, representing more than 35,000 of the roughly 63,000 Arizonans – among schools and day cares, government offices and agencies, civic groups, businesses and individuals – who signed up for the event.

The students of Yuma's Casa de Ninos preschool were among the game.

Mike Erfert, a spokesman for the Yuma Fire Department, was a hands-on instructor of 4- and 5-year-olds.

“When things move, sometimes stuff falls down. Like part of the ceiling, or... a dinosaur,” he said, grabbing a plastic crested lizard.

To stay safe from tumbling toys and other hazards, the children moved aside their orange plastic chairs and crowded under the long tables. Finding a sheltered spot is at the heart of the basic drill:

• Drop to the ground.

• Take cover under a sturdy table or desk, to be shielded from falling or flying objects, and protect your head and neck. (Be sure to stay away from windows, as another threat can come from breaking glass -- “just like Legos break,” one boy offered.)

• Hold on until the shaking stops.

Seismic events are not unknown to Yuma. A big one in recent memory was the 7.2-magnitude Easter Sunday quake of 2010. The epicenter was in Baja California, roughly 40 miles south of Calexico, but the temblor was strong enough to be felt here. This summer, less severe quakes also sent out tremors that were picked up in Yuma – a 4.7 in July, near the Easter quake's epicenter, and in August, a series of shakers up to 5.5 around Brawley.

After Thursday's “quake” was over, the little ones at Casa de Ninos emerged from under their protective tables, safe and educated.

“Good thing nothing fell on us,” another boy said.

Although Thursday was the official date to practice a drill, it's never too late for people to make a contingency plan or practice their response. To learn more about earthquake safety, go to www.shakeout.org/arizona.

Hillary Davis can be reached at hdavis@yumasun.com or 539-6857. Find her on Facebook at Facebook.com/YSHillaryDavis or on Twitter at @YSHillaryDavis.