There are no chaotic class changes at Shallcross Academy.
When it's time to move from one room to another, students walk quietly, in single file, arms stiff behind their backs. Multiple teachers and administrators step into the hallways, making sure no one acts up.
"One line!" a teacher called out recently. "No voices!"
Shallcross is one of the Philadelphia School District's 19 so-called transition schools or programs, places where students who have committed serious disciplinary infractions are educated after being removed from traditional public schools.
Since 2004, the sprawling campus for fifth through 12th graders on Woodhaven Road has been operated by Camelot Schools, a for-profit company that specializes in alternative education and runs four schools for the district. Camelot's 2010-11 contract with the district is $9.1 million to serve 883 students at several schools.
Altogether, the district is spending $19.4 million this year on its disciplinary programs.
At Shallcross, routine is crucial. Supervision is constant.
And while some parts of the day look just as they would at any other school - a spirited game of pickup basketball in gym class, talking about the potential pitfalls of credit cards in personal finance - others are decidedly different.
Adults eliminate or control situations where students might be tempted to misbehave, from the highly structured class changes to dismissal, when youths are released one bus at a time. Students may not carry backpacks (too easy to smuggle in pills or small weapons, administrators point out) or bring supplies from home. They do not use lockers - no chance to hide contraband.
"It's a strict school," said Jamire Warner, an 11th grader who two years ago was expelled from Kensington Culinary High School for beating a fellow student so badly that the boy required hospital treatment. "You have to follow directions and do the stuff they tell you to do."
But sometimes, strict is a good thing, said Warner, a talented artist whose sights are now set on college.
At his old school, Warner said, "you could do whatever you wanted. Nobody cared what you did. Here, they want you to succeed."
Students regard their infractions as part of the past. They talk about them matter-of-factly.
Sixto Rivera, 16, an 11th grader, was removed from Washington High in the Northeast "for smoking weed," he said.
Seventh grader Saintiler Saintil, 12, was "fighting a lot" at Ziegler School in Oxford Circle.
Kristie Higginbottom, 15, an eighth grader, left Harding Middle School in Frankford "because I wasn't going to school."
Damar Alexander, 12, a sixth grader from Clymer Elementary in North Philadelphia, was removed "for fighting. I was always getting suspended. It was a bad school, I was bad all the time."
The school's population is about 350, but it fluctuates throughout the year as youths enter as their disciplinary cases dictate or leave when eligible.
Students, each of whom has an "individualized learning plan," wear uniforms - khaki pants and white shirts. Some wear black shirts, the mark of a youth whose good behavior and grades has earned him or her the right to be a "bulldog" - a member of the school's student government.
Shallcross' student-to-teacher ratio is low, about 20 youths to one adult, as compared with 30 or more students to one adult in traditional schools.
But not all students are success stories. Shallcross' daily attendance rate hovers around 70 percent. Some students say it is too strict, too much like jail.
In a math class, one boy takes notes but talks constantly, frequently interrupting the lesson, insisting on leaving the room twice to speak with an administrator outside. Another boy keeps his head down, eyes stubbornly fixed on the floor, ignoring the lesson.
But Shallcross specializes in second chances - and sometimes third, fourth and fifth chances. Students often arrive with low academic skills, low self-esteem, and behavioral issues that haven't been addressed by previous schools, said Cory Thames, the school's executive director.
"I've been in mainstream schools," Thames said. "Kids do one thing wrong and they get rid of them. They come here already feeling defeated."
In rare cases, a disruptive student is transferred out, but more often, the young person stays, and the staff works out a new strategy.
"We're going to work with every student," said Thames. Often, administrators said, that includes finding services for students.
"A lot of the time, we have IEPs [special education plans], paperwork that's out of compliance," Thames said. "I don't know how they're getting away with that at other places, but we comply."
Take the case of Angel Reyes, an 11th grader who is hearing-impaired. He has needed a sign language interpreter for years, but didn't get one until he came to Shallcross, officials said.
What Shallcross does is a matter of life and death, administrators say.
"We have to train them to be successful. Some of them don't really even understand how to act in a classroom," said Milton Alexander, a Camelot executive.
"They are teenagers," added Thames. "They can make choices to rob, steal, kill, sell drugs. We have to teach them to make good decisions."