WARWICK — About three dozen parents and students from high schools around Rhode Island gathered in the lobby of an office building Sunday to get a taste of how the other half lives . . . or at least, eats.

The event was organized by Plan USA, a group that tries to increase student awareness of world problems, and Youth United for Global Action and Awareness, a national student group that tries to help solve them.

Elizabeth Murphy, coordinator for the event, said the idea behind the exercise was to show people who live in prosperous parts of the world how powerless those in less-well-off areas are to arbitrary events that affect their access to things as basic as food.

In the lobby of Plan USA’s offices off Jefferson Boulevard, the participants were broken up into three groups. One group represented the 15 percent or so of the world’s population that is considered upper class.

They sat in five high-backed chairs at a table with an ochre table cloth and a flowery centerpiece. They got cheese ravioli, homemade rolls, salad and a choice of three beverages.

At the table representing the middle class, there was no table cloth and not enough chairs for the seven who sat there. They got peanut butter-and-jelly sandwiches and juice or water.

For the low-income group, about 65 percent of the world’s population, there were blankets and a woven mat. The only beverage was water and the only food was saltine crackers.

After a few minutes of eating the meals they were allocated, the lobby’s microcosmic version of the world economy suffered some jolts. A severe drop in cocoa prices led to one of the people at the upper-class table getting a bonus, because his chocolate company had higher earnings off the price drop.

But at the middle-class table, the cocoa price drop was bad news. A cocoa grower got laid off because his employer couldn’t afford to keep so many workers on the payroll, and he had to move to the low-income group.

Jan Peterson-Rothstein, a parent, was part of the low-income group. She said it was frustrating to sit on the floor with a jug of water and some crackers while watching others get served ravioli and rolls by waiters and waitresses.

“I thought we should rise up,” she said, “but with what? What energy? What resources?”

Allegra Marra, a senior at Cranston High School East, said the exercise communicated the issues of world hunger more effectively than a speaker from a lectern.

“It’s something that can be overwhelming,” she said. “You have to put it in a way people can understand.”

At the end of the event, another Plan USA manager, Kate Ezzes, had one last ironic plea to the participants. There were still some sandwiches and raviolis left that shouldn’t go to waste, she said.

“Please,” Ezzes asked, “take some food home with you.”

jhill@projo.com