Andre Waite took a deep breath and wedged a crowbar against a piece of rotting wood. A sharp tug, a cloud of dust, and the piece came free.

"Good," instructor Sam Ginsburg told the Bok High School junior last week. "That's it."

Piece by piece, Waite and a group of students from the vocational high school are pursuing an unusual after-school activity: rehabbing a South Philadelphia rowhouse, a former drug den, with their own hands. For two hours a day, five days a week, the students strip floors, frame walls, install plumbing, paint rooms, and lay tile.

But the members of a construction after-school club are also learning about the value of a job done well, the satisfaction of transforming a neighborhood eyesore.

"I am proud of this," Waite said. "I want to get this house finished."

District Attorney Lynne M. Abraham, who brokered the deal to sell the house to the after-school program that runs the construction club, said she was wowed by the work of about a dozen students.

"They're a wonderful group of young guys," said Abraham, who visited the students at the house in April. "This keeps them out of trouble, gives them job skills, and restores a neighborhood that has been blighted by this drug house."

It all began when Loretta Crea, a founder of Sunrise Philadelphia Inc., an after-school organization, heard that the city was selling a seized house to another nonprofit. She wrote to Abraham, asking whether Sunrise's students could have a house to work on.

Abraham agreed, and the city sold the first house to Sunrise for $1 in 2003. It took Bok students four years to gut and remodel the modest structure, but when it was done, officials sold it to a first-time buyer for $75,000. That money was put aside for supplies and salaries - the students earn $5 hourly for their work - and for the house they are fixing up on Cantwell Street, a few blocks from Bok, at Ninth and Mifflin Streets.

The district attorney said the house was seized in a drug prosecution.

"Sometimes the houses are so bad they have to be torn down," Abraham said. "Sometimes, with hard work, they can be saved."

Al Sorichetti, chief executive of Sunrise, whose offices are housed at Bok, said the group planned to equip the house with computers and use it as a center for luring dropouts back to school.

When Sunrise took possession of the house in January, it was a sight: exposed wires dangling everywhere, graffiti scrawled on walls, copper pipes missing. The tiny yard was crammed with old car parts, trash, and other junk.

There was no electricity, water, or gas. At first, the students worked with flashlights and battery-powered lamps.

Ginsburg, a retired Bok educator, now volunteers for Sunrise, and is on site every day. He's aided by club member Eric Schreiber, the most experienced student, who functions as foreman, parceling out jobs and tackling the toughest work.

"It's good experience to take a house that was in such bad condition and turn it into something much better," said Schreiber, 18, whose father owns a contracting business and who plans to work in the industry.

Kiry Mark, 18, a senior, had never picked up a hammer before a friend recruited him to the project.

"I've learned a lot so far, and I'm still learning," Mark said, pausing from sanding a spot under a kitchen window. He plans to use his skills to work construction jobs for a year before he decides what he wants to study in college.

Ginsburg, who spent his career teaching special-needs students vocational skills, is patient with the 12 to 17 young men who show up on any given day. He never loses his cool, even if a ceiling patch has to be redone three times or he has to coax a student off a ladder to put on his goggles, again.

The house is for learning, he said. Eventually, the students will get it right.

"They'll do anything I ask them to," Ginsburg said. "They're good kids."

For years, school districts have been disinvesting in vocational education; shops that were once thriving are now often shuttered. But college is not for everyone, Ginsburg points out, and even for those who do go on to higher education, it's valuable to have the skills to build and maintain a home.

Many of the members of the construction club, who study trades ranging from business to computers at Bok, say they do want to go to college. Others say they'll work in the construction field right away or go on to technical colleges.

The house project is a powerful tool against truancy, said Crea, the Sunrise cofounder.

"If they want to work after school, they have to show up for class," she said.

The students' work on the house means long days. Waite, for instance, has a 90-minute bus ride home to West Philadelphia, and often arrives home after dark. Many go straight from the construction site to another job, and they have given up school holidays to make progress on a particular project.

In the living room, Ginsburg watched over Waite and Denny Huon, 16, a junior, who was trying to remove part of a wall leading to the basement. The plan was to pull out the old, unsound structure and replace it with a new one, plus a door, but Waite and Huon looked a little unsure.

"Just watch the other wall, guys," Ginsburg told them calmly as they picked up tools. "Make sure you don't hit the other wall."

A little more coaxing, some well-placed crowbar work, and the mission was accomplished. The pair moved on to the next task. Also on the agenda for the day was priming the kitchen, framing a wall, hanging a door.

Andrew Meak, 16, a junior, paused from prepping the kitchen for its paint job.

"Maybe it's a guy thing," he said, shrugging. "I really like learning how to do stuff."