Muhammad knows a few things about struggling schools, and about good ones, having attended and taught at both kinds himself. He was born in the Bedford-Stuyvesant section of Brooklyn, N.Y., at a time when his parents rarely felt they could let their eight children play outside.
Schools there were "horrible - we did nothing all day," he said. "I mean that literally. We'd play cards all day. I was a smart kid, but your environment is everything."
As his parents entered and completed college, then got jobs as a teacher and a social worker, the family moved several times. By the time Muhammad was in high school, they lived in Merrick, on Long Island, where he attended a well-regarded public school.
He struggled at first, until a teacher saw something special in him, recognizing his strengths and challenging him to do better.
That made all the difference for Muhammad. He saw that it was OK to know the answers. His grades became stellar. He joined the Model United Nations team. Eventually, he landed at New York University, where he thrived as an economics major.
When he graduated from college in the early 2000s, Wall Street wasn't hiring, so Muhammad's plan to become a stockbroker was scuttled. He and his wife moved to Philadelphia, her hometown, and he became a math teacher at Olney West High School.
His students, he quickly realized, were bright but raw. When he formed a chess team and took them to competitions, they showed up unprepared, he said, and "they didn't know you can't talk trash over the board."
But they learned fast and won trophies. He created a program to pull promising students into higher-level math classes. Eventually, he moved to prestigious Masterman and enrolled in a Lehigh University program that prepares principals to remake urban schools.
Teaching at Masterman taught him a profound lesson, Muhammad said: The young people at the city's premiere magnet school were more polished, perhaps, but fundamentally they were no different from the students at Olney.
"This theme will take me to my grave: Opportunities," he said, "make better kids."
Since 2011, Muhammad has been assistant principal for operations at Universal Audenried Charter High School. When he heard of a job opening at Bartram - where he'd worked as an intern principal - Muhammed felt called.
Bartram had become synonymous with dysfunction. Some had written it off as a wasteland.
If anything, he said, that makes Bartram a better fit:
"Everything needs to be built."
Dion Betts, the assistant superintendent responsible for Bartram, conducted a national search to fill the position. He was intrigued when he met Muhammad, but worried that the math-lover with a formal manner and booming voice might be too serious.
Then Betts and a Bartram teacher observed Muhammad at Audenried, where they were impressed with his rapport with students and how he jumped into a class where a substitute teacher was struggling.
Muhammad taught part of the lesson himself, modeling for the substitute an effective way to get the class back on track.
And, as important, "Ozzie likes him," Betts said.
That's Ozzie Wright, the respected retired principal brought to calm things down when Bartram was in crisis.
In a matter of months, Wright and a full complement of police officers and other outside aid ended the hall-walking, the routine fights, the brazen smoking and drug use.
Wright will mentor Muhammad, working part-time over the summer and fall, to help the new principal transition into the job.
Wright likes that Muhammad is listening and has advised him to use some of the tools he has used so effectively himself - "going back to the basics," Wright said. "Greeting students outside, being present in the classrooms, the hallways. Always talking to people."
Muhammad has set lofty goals.
"I tell kids, You want your school to be like the ones you see on TV" - schools with rich extracurricular activities and a culture of academics - "but we've got a lot to do to make it look like that."
The tumultuous year has taken its toll on Bartram. A number of staff members retired or got out. Muhammad believes that the school has some good teachers, but that its instructional practices are inconsistent.
And while the school is no longer in crisis, student behavior certainly still needs attention. A few weeks ago, Muhammad was introduced to sophomores and juniors in an assembly.
Some ignored him. Others catcalled. "Their decorum is lacking," he said, "because they haven't been given a reason to show decorum."
Muhammad figures his job is to discover the strengths of his teachers and to build on them. He plans on saying "yes" to every offer of help.
He knows that speeches won't win any hearts or minds. He knows that he and the staff must show, not tell, students what Bartram can be like, that they must make young people want to come to school. He knows that promises have been made and promises have been broken.
The district's dire budget situation will cast a shadow over Bartram, just as it will every school. When Mayor Nutter visited the school in the spring, he warned the teachers that "we'll be lucky to be funded to continue this level of inadequacy," said science teacher Antoinette Calimag, one of the staff members who met with the mayor.
Muhammad is philosophical about the budget woes, though.
"Money does play a big part, but not having it just makes the grass a little patchier," he said. "This isn't a desert. There's green - you just have to jump from place to place to get it."
Muhammad's staffers are committed, they say, and want to work with him to make the school succeed. But they're also battle-scarred and a little wary. He is the fourth principal since September.
The improvements under Wright were encouraging, teachers said, but they know they came in part because of resources that may well go away.
"A school this size, if we don't get the support, the resources, it's going to be difficult for one man to turn this around himself," said Harry Brubaker, a math teacher and 10-year veteran of Bartram.
But there are signs of hope, too. Calimag, a science teacher and the school's teachers' union representative, was cheered by the fact that Muhammad stuck around for hours after a community meeting Wednesday to talk with staff members.
"He wanted to understand the challenges he's going to face," Calimag said. "He does have a vision, and he wants to articulate it to the staff, and that's reassuring. He is hopeful."
The thing is: Even knowing the daunting odds, Muhammad is choosing Bartram, and that's something.
"I would say," Calimag noted, "we are cautiously optimistic."