For the last several years, there have been no split classes.
Leveling also happened later than usual this year. Officials said they needed extra time to work through the complications of the budget crunch. Teachers' union officials say the delay was unnecessary.
Principals for the first time were permitted to use factors other than seniority when making their staffing adjustments. District officials said they did not immediately have data on how many leveling moves bypassed seniority rules.
Superintendent William R. Hite Jr. said in a statement that the changes were painful but necessary, and would help overcrowding in several schools, "providing better learning environments for our students."
"Leveling is an opportunity to address enrollment concerns early in the school year," he said.
But many see leveling as disruptive. Protests both formal and informal erupted at schools around the city in the last few weeks.
At Cook-Wissahickon Elementary in Roxborough, a large crowd turned out to voice displeasure over the process, in which two teachers left the school and a split third- and fourth-grade class was added.
At Vare-Washington Elementary in South Philadelphia, a group of parents and teachers protested the loss of multiple staffers.
Yvette Chandler, a parent of two daughters who attend Vare-Washington, was part of the group that was outside the school last week.
Chandler's older daughter is in a special-education classroom that used to have two teachers. Now, she said, there is only one. Other classes at the school are overcrowded, she said.
"The kids don't understand why many of them are being overloaded," Chandler said. "Do you see how much they're trying to do to discourage us? Pretty soon, there's going to be more dropouts than ever."
District-wide, the changes are causing a ripple effect. Parkway Center City, a magnet high school, lost one teacher, but class schedules were shuffled for almost everyone. Some students who had been enrolled in Spanish lost the class and will have to take the subject in another year, one teacher said.
Social studies teacher Dave Thomer lost one section of world history and picked up a section of ethics in its place.
"I have to do enough in the next three weeks that I feel comfortable giving kids a grade," said Thomer. "I'm starting from scratch, seven weeks into the school year."
Backed by a strong school administration, Parkway Center City is making do - teachers pitching in; aides working extra, unpaid hours; students volunteering as office staff - "but it's incredibly frustrating," Thomer said.
At AMY at James Martin, a middle school in Port Richmond, math teacher Rick Haas spent seven weeks building relationships. But he worked his last day there Friday. The school lost two teachers, including Haas, and every student got new rosters.
Students started a petition to save Haas and the other teacher who was bumped, but there was no response from the district.
Haas reported to Penrose Elementary on Monday, reluctantly starting over almost three months into the school year.
"Going in, I had nothing prepared. I didn't even know if I had a classroom," Haas said. He's going to make the best of it, Haas said, but is concerned about the students at his old school.
"These kids have to get grades," Haas said. "Some of them are struggling, and they need support."
Philadelphia Federation of Teachers president Jerry Jordan, who welcomed the reduction in split classes but said it did not go far enough, believes the changes came far too late.
"It's in everyone's best interests to make the adjustments as early as possible," Jordan said. "The district could and should have leveled two weeks ago, as scheduled."
BY THE NUMBERS
Teachers moved to new schools, compared with 82 last year.
New teachers hired, compared with 42 last year.
Classrooms split between two grades, down from 100.