MOLENA, Ga. -- If the grimace and sweat streaming down Danielle Jackson's face didn't illustrate the challenge she was enduring, her persistent grunting did.

Maneuvering along the mucky route of a timed mock cross-country rescue through dense woods with a 35-pound rucksack strapped to her back, the South Gwinnett (Ga.) High School Cadet had been navigating the course decently.

Until she reached the low-crawl portion of the course -- a 20-yard scooch along a berm that quickly went downhill.

Seemingly pinned down by the added weight, Jackson struggled to pull her way through. She stretched out her arms, trying to use the ground and her legs to propel her forward. But she could only move a few inches at a time.

Finally, when she emerged several moments later, exhaustion set in. Her shoulders slumped. She gasped for air.

But she tightened the rucksack and trudged ahead. The finish set just a couple hundred feet away.

"I didn't expect it to be that tough," a relieved Jackson said after the event. "That rucksack was killing my back. I'm just glad it's over."

Saturday's Junior ROTC National Raider Challenge Championships put Cadets to the test -- physically and mentally. Up against a number of obstacles, Cadets relied on their abilities -- and each other -- to succeed.

"This is draining," said Alton Wheeler, of Stephens County (Ga.) High School. "But we all have to stay motivated."

Thirty-five schools from 14 states, most of them Army JROTC programs from as far away as Wisconsin, have come to the Gerald I. Lawhorn Scouting Base this weekend looking to dethrone last year's champs. Francis Lewis (N.Y.) High School captured the male and female divisions, while Smith-Cotton (Mo.) High School won the mixed-gender title.

Winners will be announced Sunday after individual Raider competition.

Cadets on Saturday tackled five events: a fitness test consisting of two minutes each of push-ups and sit-ups, a team 5k run, one-rope bridge, the cross-country rescue and something known as the Gauntlet, where teams race along a mile-and-a-half-long course over rough and hilly terrain while carrying four 35-pound rucksacks.

For several teams, the one-rope bridge proved particularly difficult. Unlike last year when its water could cover Cadets up to their waists, the creek they were required to cross contained only large puddles of water and a mostly muddy floor.

Several teams still finished the event soaked.

What tripped them up wasn't the crossing, but improperly strung rope bridges that sagged from not being tied tight enough between trees on opposite sides of the creek. At one point, the male team from Smith-Cotton had three Cadets lying in the mud in the middle of the creek bed, their collective weight forcing them down.

Richmond Hill (Ga.) High School didn't fare much better, in terms of keeping dry. One member of its mixed team cried out as her back raked the chilly water.

Devin Oliver was among the fortunate. He was one of the few Richmond Hill members who made it across still dry.

"I was lucky," he said.

Oliver chalked up the problems to inexperience constructing rope bridges at such distances -- in this case about 100 feet or so.

"We're just not used to practicing that distance," he said.

One of the newcomers to this year's meet was Stephens County. Cadets had wanted to compete last year, but being a program now only in its third year, retired Lt. Col Phil Baker, the senior Army instructor, simply didn't feel they were ready.

But after Cadets placed third in the Georgia state Raider meet recently, he let them enter.

That pleased students like Jacob Schuster, a sophomore. After performing 129 push-ups and 86 sit-ups in the school's first events Saturday, he was winded but excited.

"We feel we'll be competitive," he said.

Schuster preferred starting the day with a fitness test, rather than midday or later. He said he believed his strength would have been sapped after the other events and ultimately hurt his performance.

Stephens County has practiced routinely the last few months readying for the Raider National. Schuster and Wheeler said they thought the success at the state meet would spill over.

"Through practice, we work hard to make sure we make no mistakes and constantly motivate each other," Wheeler said. "If we had quit then, we'd do the same thing at this meet."

After finishing third in the female division in 2010, Hannah Petty, of Grissom (Ala.) High School, didn't just want to improve her team's standing this year. She wants to win.

The route to victory included the daunting trek up a hill that rose about a couple of football fields in length as part of the Gauntlet task. Recovering afterward, Petty was matter-of-fact about the event.

"This is no fun," she said. "You try to practice for the really big hill, but there are no big hills like this to practice" on in Huntsville, Ala.

But Petty, a senior, wasn't going to let such a challenge stand in her way of going home a winner with teammates she refers to as "family."

"This is my last chance," she said.