The four Mendelson children of Potomac have been attempting to sleep under the stars this week, bundling up in blankets and sleeping bags inside a "house" with green tarp walls and a roof of pine branches.

Before bedtime, stories are read to Raffi, 2, Noah, 5, Hannah, 8, and Max, 9. That comes after friends and family join the Mendelsons for dinner on the plastic patio table inside the structure they built and decorated last weekend.

This Orthodox Jewish family, like many other Jewish families in Montgomery County, is doing a mitzvah, a good deed, by building and then "living" in a sukkah, a temporary structure that is built for the eight-day festival of Sukkot (pronounced sue-coat), which ends Tuesday.

Sukkot teaches "that our homes do not define us, that we get our greatest joy from our family and our God, not the shell of our home," said Rabbi Mendel Bluming of Chabad Shul of Potomac, an Orthodox congregation.

Sleeping in the sukkah, "You're supposed to feel like something might happen to you but it would all turn out okay," said Max, eating the pretzel roof off a miniature, edible sukkah.

Sukkot is all about perspective, according to Bluming. It's a powerful lesson as people watch the devastation of Hurricane Katrina, the earthquake in Pakistan and the South Asian tsunami, he said.

Jews celebrating Sukkot will eat their meals in their sukkah, a structure often built of wood but also sometimes plastic piping. There are dozens of rules for building the sukkah. For example, the dwelling must have certain dimensions and openings; those who gather inside it must be able to see the sky through the roof.

On Sunday afternoon, Martin Mendelson, 40, who started building his family's sukkah earlier that day, wielded a hacksaw and cut down pine branches to put the finishing touches on the roof. It took three of his children -- 2-year-old Raffi watched -- his wife and his brother a few hours to assemble their wooden sukkah with walls of tarp, a roof of branches and harvest-style decorations.

"It's pretty," Hannah said. "It took a lot of hard work. When I look at it, it looks like I did hard work."

Her mother, Julie, 38, added that the work of cooking for Sukkot and building the sukkah is part of understanding the holiday. "You persevere because this is what our forefathers did," she said. "I like our sukkah because it requires some work."

Although they purchased the wood at a hardware store, the brackets and screws for the Mendelsons' sukkah came from a kit, "The Klutz-Proof Sukkah Project." It's the brainchild of former Duke University psychology professor Steve Henry Herman, a Conservative Jew who developed the kits for Jews who did not build their own sukkahs but used the community sukkah at their synagogue.

Herman, 58, who started helping neighbors build sukkahs in 1990, now sells about 1,000 sukkah kits a year in 25 varieties and sizes.

"Sales in the D.C. area went up immensely last year, by 150 percent," Herman said. "No other area went up by more than 20 percent. Maryland and D.C. are going to be our biggest sales area this year too -- bigger than New York." Herman said he is surprised by the trend and can't explain it.

But Rabbi Stuart Weinblatt of Congregation B'nai Tzedek in Potomac said he has seen the trend for some time.

"It's an interesting phenomenon that's taken off in the last 15 or 20 years," Weinblatt said. "In the '40s, '50s and '60s, people were hesitant to publicly display their religious affiliation, so the sukkah became confined to the synagogue, the community sukkah." In the early 1970s, there was a resurgence in ethnic and religious pride, he added, and "nowadays, [the sukkah] becomes an advertisement of pride."

In Montgomery County, there is a lot of advertising. Sukkahs have popped up in numerous neighborhoods, particularly those near Orthodox Jewish synagogues. The rectangular-shaped structures come in many sizes and are often wrapped in tarp and topped off with bamboo mats or tree branches. They're filled with family gatherings and prayer.

Part of the holiday "is celebrating the strength of our connection to family and friends," said Rabbi Warren Stone of Temple Emanuel, a Reform synagogue in Kensington. "The message of Sukkot . . . is ancient wisdom which speaks to the heart of the modern Jewish family."

This is the first year that the Jacobs family of Rockville has built a sukkah. "I always hesitated to have a sukkah because I thought it was too much," said Meredith Jacobs, 38, a member of B'nai Tzedek. "But then I realized it was such a festive holiday. I wanted [my children] to have that memory." For Paula Sayag, 44, of Brookeville, building a sukkah is about building on a memory.

"As a child I remember it was a lot of hard work, but it was still a wonderful time with my father," said Sayag, the mother of three and a Conservative Jew who has been building a sukkah with her husband and three children for 15 years. "Now it's becoming easier, and that may or may not be a good thing, because the hard work is part of it. After all, it wasn't easy for our forefathers."

Remembering history is an important component of Jewish holidays and festivals. Sukkot reminds Jews that for 40 years the Israelites wandered in the desert before entering the land of Israel. In addition, the festival celebrates the fall harvest.

Sukkot lasts for more than a week because "that's what the Torah tells us," said Weinblatt, who added jokingly, "If you're going to go through all the trouble to build it, you might as well sit in it for more than one day."

Martin and Hannah Mendelson place bamboo shoots on the roof of their sukkah, where they were to sleep for eight days to commemorate Sukkot, which ends Tuesday. Above, the Mendelsons' backyard sukkah in Potomac. Below, Hannah, 8, and Noah, 5, help their mother, Julie, decorate the sukkah.Noah Mendelson, 5, makes a candy sukkah out of graham crackers. Hannah, 8, below, examines some of the decorations. One seller of sukkah kits said sales in the Washington area went up 150 percent last year.