When one pioneer wagon busted its axle on the first grassy hill, the elders split off from the wagon train to assess the damage. After much fiddling and discussion, it was decided that two of the most able-bodied would venture off the 18th century-style westward trek -- to the nearest 20th century hardware store.

The broken axel was just one of many travails that beset the 108 fourth and fifth graders of Olney Elementary School who embarked last Friday from the school's parking lot for Rockville to recreate in a day in the westward movement of the 1840s. They are studying that part of history in school this year.

The autumn sun made the moist cornfields of Olney and patches of wildflowers glistened as the group set out, accompanied by parents and teachers, pushing and pulling small wagons that had been redecorated to look like prairie schooners. They stayed away from paved roads and took to the tough terrain.

A dirt road spotted with giant mud puddles, and a meadow of slippery, wet grass were tricky obstacles for the pioneers, and wagon partners quickly shifted positions, lifting the wagons' back ends, pulling on front wheels, and trying to avoid spills.

There was a row of new two-story houses at the edge of a cornfield in the otherwise rural scene. But the students, deep into their roles, took no notice.

"We're going to build a house and take a blacksmith's job," said 9-year-old Darrell Sampson, who was portraying a character from the past. His character, he said, has a 15-year-old son and ends up in Oregon. The family set out with "some oxen and a few cows," he said.

Darrell and the others explained to those they met along their five-mile journey to the Lathrop E. Smith Environmental Center in Rockville that they were leaving the East Coast "because of bugs . . . and termites . . . "

"This is really a problem-solving experience related to the curriculum itself," said fifth-grade teacher Debbie Ambrose, as miniature wagons with signs proclaiming "Smith Center or Bust!" and "God Bless This Wagon" rolled by. "They have no idea what they're up against.

"By the end of the day they will be dragging and tired," she said. "Then they'll get there and realize they're not done. They still have to cook their meal." The group spent the night at the center, but inside.

In all the group had to traverse six streams, maneuver down a steep hill at the back of the Norbeck County Club golf course and cross a bridge that had no railing before they reached the center, where they would spend the evening by a campfire.

"They had wagons tip over, they had wheels come off," said Karen Nordahl, a teacher. "There were a few sore feet. And a few forgot their lunches."

The students worked for a month in small groups to design and build their wagons, most fashioned with wire and sheets, and several with indispensible masking tape. They also planned their meals, keeping in mind that whatever they intended to eat, they had to lug with them.

"We used sticks with some wire and holded it with tape," said 9-year-old Sang-Ho, looking suspiciously at his group's wagon, bulging and tipping with supplies.

"We tested it yesterday and the shell came always down. We might have too much stuff. . . . We have homemade biscuts, applesauce, gingerbread . . . eight chickens and four horses," he said, slipping into the personage of Tony Wilson, a farmer from "India -- no I think it's Indiana."

When the pioneers reached trail's end they feasted on vegetable stew they cooked themselves and chicken the elders had prepared earlier.

As night set in and the campfire was lit, apple cider was poured and fresh popcorn crackled, a gruffy stranger -- better known in the region as storyteller John Spelman -- appeared from the direction of the now-darkened trail and exchanged a few tales for a warm meal.