BOWDOIN COLLEGE GRANT EAST TOWNSHIP — In the 77 years since the Appalachian Trail was completed, only 15 families with young children have finished an end-to-end “thru-hike” of the 2,160-mile trail stretching from Georgia to Maine.

On Monday, a Maine family is expected to become No. 16 when its four members reach the summit of Mount Katahdin in Baxter State Park. But for David and Emily Kallin of Dresden and their two children – Nathan, 9, and Maddy, 8 – this five-month hike is part and parcel of who they are: The Kallins plan their lives around outdoor adventures.

Each year the family takes a trip, chosen by the children, during April school vacation. Last year it was a 120-mile bicycle trip to camp in Acadia National Park. In February, they take an annual trip in Baxter State Park, skiing 14 miles to their campsite.

Now the Kallins are about to make the record books at the Appalachian Trail Conservancy.

“It is unusual, especially a young family,” said Carol Wellman of Wisconsin, a ridge-runner with the Maine Appalachian Trail Club who met the Kallins in Maine’s 100-Mile Wilderness last week.

“I like the fact that the boy has a five-pound pack,” Wellman said. “He gets to be a part of the group. If kids are overwhelmed they will hate it. If they participate, they feel included. It’s a fine balance.”

The Kallins decided to do the hike this year because they thought Maddy would be old enough to complete the trail. David and Emily hiked it together after college in 2002 and vowed they would one day repeat the journey with their children.

David’s employers at Drummond Woodsum gave him a leave of absence from the law firm on the condition that he blog about the hike, which he has done at Kallinfamily.com.

So the children were taken out of Dresden Elementary School two months early this spring and home-schooled on the trail. It turned into a better classroom than their parents imagined.

“They kept up their schooling with essays, and learning about plants. And they memorized poems,” David said. “But a big part of their learning has been learning from others, from people other than us. It’s something I did not expect.”

They met a beekeeper, a snake handler, a Minnesota fishing guide, and an investment banker-turned-long-haul-trucker who taught the children to play Texas hold’em poker with Skittles.

“The kids were asking a college graduate on what his thesis was about. He was telling them about the theories of economics,” David said.

The family hiked 10 miles a day after starting its journey on March 31, but that daily distance quickly increased. Emily Kallin said the children’s interest in other hikers inspired their pace.

“Maddy would fall in behind a 6-foot, 20-year-old guy and hike behind him chatting away, telling him her life story,” Emily said.

Other hikers learned of the family through the log books found at hostels along the trail. From Nathan’s 9-foot fly rod to Maddy’s pink rhinoceros-shaped walking stick she named “Pinkanoceros,” the family that blogged about their trip became known by hikers from Georgia to Maine.

“We had heard of them. It’s nice to see young children out here. It’s endearing,” said thru-hiker Adam Joseph of Hudson, New Hampshire, who met the Kallins on Tuesday in Gulf Hagas, a gorge area along the trail in central Maine.

For their adventure, they each brought a set of light clothes and a set of warmer clothes, including down jackets they would mail back and forth to members of their extended families. They each went through three to four sets of minimalist running shoes.

Somewhere in Tennessee, Maddy and Nathan became intrigued by older hikers they saw sleeping in hammocks, so the family bought a display model at a store that the children shared. By Pennsylvania, Maddy and Nathan each got their own hammocks, and slept like two giant insects wrapped in cocoons.

David and Emily carried the bulk of the gear, including a tablet computer, but Nathan and Maddy carried their hammocks, and Nathan his fly rod and clothes. Orion, the family’s mixed-breed dog, carried 3 to 6 pounds of his own food. Then at night he held watch over all their food, sleeping next to it.

“He kept any rodents, red squirrels and bears away. We didn’t see one bear,” David said.

David and Emily estimated the cost of their hike at $8,000 to $9,000.

They had a town meal twice a week at a restaurant, and stayed in a hotel about three times a month. They spent roughly $1,000 a month on food. Homemade meals were supplemented with dehydrated farm-fresh food from the family’s garden that Emily prepared for the trip and arranged to pick up along the way.

Occasionally, Nathan caught fish for the family with his telescoping fly rod. The fold-up rod had 3 feet of line at the end – and no reel. A seasoned angler who learned from his grandfather in the Belgrade Lakes, he pulled the line in hand over hand. In one instance, a sizable trout ended up in a dinner of fish tacos.

“It was a rainbow trout,” Nathan said proudly. “One day I caught at least 25 sunfish.”

On Monday, the adventure will end when the Kallins’ long-distance hike is completed five to six weeks ahead of schedule.

Their last stop will be Abol Campground in Baxter State Park, where they will wait and head for the summit after the conclusion of the Penobscot tribe’s “Katahdin 100,” an annual pilgrimage up Mount Katahdin.

On a trail where people often seek out nature to get away from society, the greatest lesson the Kallin children have learned is how connected they are to others – and how much they have to share.

“Call me Ishmael” is one story. Many thru-hikers this year heard the tale of the 8-year-old girl who could recite the first page of “Moby Dick” perfectly.

When Maddy didn’t have a new friend to talk to, she spent her time on the trail memorizing poems and the first page of Herman Melville’s novel. Her mother had done the same with her father years earlier.

Five days from the family’s summit day, Maddy recited the passage from the famous novel for one more hiker, speaking of an epic adventure to “see the watery part of the world” – which her father pointed out is a lot of what Appalachian Trail hikers find in Maine.

It’s one of many lessons she’ll take from the trail.

“I’ll probably miss the trail a little bit,” Maddy said. “Well, I might miss meeting new and interesting people. Being at home and not hiking will be a change.”