The two teenage girls worked as intently as structural engineers as they built their first gingerbread house.

They were almost finished when a piece of the roof started to fall and an emergency dollop of icing was used to shore it up. The girls then got the idea to use a hairdryer to quickly dry the icing seams.

They wanted their house to be picture-perfect, like the ones that fascinated them when they visited a display at PPG Place, Downtown. It was the first time they had ever seen gingerbread houses.

The girls, Purity Wahu, 17, and Jane Wanjifu, 18, are from Kenya and on their first trip outside of the country. They are residents of Hekima Place, a home in Nairobi for girls orphaned by AIDS and other poverty-related issues. The home was started in 2005 by former Mt. Lebanon resident Kate Fletcher.

On Nov. 30, Mrs. Fletcher brought the girls to her hometown for a visit that has been packed with parties, trips and new experiences all hosted by Mrs. Fletcher's supporters in the area.

"I love all of the parties," Purity said. "And the [Christmas] decorations, I really like the decorations."

Purity and Jane, who both speak English, were chosen for the trip from among the 46 girls at Hekima Place because they are the home's top students.

Their first impression of Pittsburgh: "It's cold," they said in unison a few days after their Nov. 30 arrival.

It's the first time they've experienced temperatures below 40 degrees and the first time they've ever seen snow.

Purity said she found the area to be "a good place.'' Jane called it "a beautiful place."

They said they were at first confused by trees that had no leaves. In Kenya, the trees stay green year-round.

They were also surprised that homes in the area are built with bricks and include indoor heat. In Kenya, they said, most homes are made from sheets of metal and have no heating system. Temperatures there rarely drop below 40 on even the coldest nights, they said.

Carol Rothermel, of South Fayette, and her son, Eric, 12, hosted the girls for the gingerbread-making session on Monday. Earlier in the day, they took Jane and Purity to Sarris Candy store in Canonsburg, where they took delight in the displays of colorful jelly beans.

The girls are staying with the family of Janet Hauge, of Upper St. Clair, who was among a handful of women who visited Hekima Place for five weeks last spring. Mrs. Hauge, an avid Steelers fan, has taught the girls about Pittsburgh's love affair with its football team.

The girls joked that they don't really know a lot about the game of football, but that they've learned that watching it involves a lot of yelling. On Sunday, they will attend the Steelers game as guests in the Rooney family luxury box.

Last Sunday the girls were hosted at a brunch by Gracelyn Ratay, a former school director in Mt. Lebanon, who also invited girls from Mt. Lebanon High School.

The Mt. Lebanon teens were awestruck when Purity and Jane told them they get up each school day at 4 a.m. and are at their desks by 5 a.m. to do several hours worth of preparatory work before classes start at 8 a.m.

They described their days again during a more formal session with students at Mt. Lebanon High School on Tuesday mornings.

Jane told the students that the boarding school the girls attend has no hot water and because of that "mornings are a bit challenging."

She said students at her school take 11 subjects, including three science classes, and that classes are held for part of Saturdays. Much of the free time they have is spent studying to keep up with their classes.

They told the Mt. Lebanon students the most impressive sights they've seen on their visit were the dinosaurs at The Carnegie Museum and the "BODIES" exhibit at the Carnegie Science Center.

As for the dinosaurs, "I've read about them in books, but now I know they really existed," Jane said.

Of the Bodies Exhibit, they marveled that they were able to see embryos at each stage of gestation and the entire digestive tract.

Among other places they've visited during their trip is the American side of Niagara Falls, which they visited last week during a trip to a Hekima Place supporter who lives in Buffalo.

That trip marked the first time they wore hats, gloves and scarves, along with heavy coats to stay warm.

On the way back to the area, they stopped to visit Gannon University. Both girls would like to attend college in the United States. Jane is interested in physics and would like to become an electrical engineer. Purity is interested in writing but would also like to become a psychiatrist.

Of their whirlwind trip, which ends Monday, Purity said: "We are somewhat tired, but we are really, really enjoying it."