Several dozen Chester Upland district high school students - angered by what they said were standing-room-only classes, some with teachers they said were not properly qualified, by overcrowded buses, and by chaotic schedule changes - walked out of a magnet school Tuesday morning.

The students, from the 725-student Science and Discovery and Allied Health High School, then marched two miles to the district administration building. They went there to add their voices to a news conference by the NAACP on the effect of state budget cuts on the district.

Joyce Wells, the district's acting superintendent, said Tuesday afternoon that the school was going through "an adjustment period" with fewer teachers and a newly combined campus for the two schools this year. But, she said, the problems were on their way to being ironed out.

She said that all teachers had proper certifications and that class sizes were being adjusted. She said she had not heard about bus overcrowding. "We are making some corrections as we make our transition," she said.

This summer, the district, hit hard by cuts in state and federal aid, laid off about 40 percent of its teachers. That left only 20 teachers at the Science and Discovery and Allied Health schools. They were combined because of the budget cuts and are situated at the former Showalter Middle School campus in Chester.

The number of students who joined the protest was in dispute; several participants said 40 to 45 of them walked out. District officials said their attendance figures showed about 30. They were back in class by noon.

Destiny Sharp, a Science and Discovery senior, said that many classes had about 40 students but that one nursing class had 75. Students were standing or sitting on shelves around the walls, she said.

She said one computer-science teacher had an art certification. Student schedules had been changed several times, she said; some classes were being taught by substitute teachers, and "they're just baby-sitting us." She added: "There's no communication. It's chaos."

Mori Hitchcock, also a Discovery and Science senior, said that a business teacher was teaching a nursing class. Some students had been sent home early, he said, because "they told us they didn't have anything for us to do." Buses to the school were so packed, he said, that "there were three or four to a seat."

Wells said that no classes had 75 students, though some ran as high as 42. One classroom had lacked enough chairs, she said, but that was remedied.

She said student schedules were being changed to reflect the courses they should be taking, after some had been assigned to classes that were not part of their "career path areas." There were some substitute teachers at the schools, she said, but "our goal is to put [regular] teachers in those classes."

Wanda Mann, president of the Chester Upland school board, said she was unhappy that students had left school without permission. She said some parents "were livid" about the protest.

The district has managed to keep its core programs intact despite the layoffs, she said, and overall, "it's running smoothly; things are fine."

Some parents supported the action. Clara Hitchcock, Mori Hitchcock's mother, said she was working with other parents to make sure the problems at the school are addressed. "We will give them a chance, but if things don't change, we will take action," she said.

At its news conference, the NAACP announced a Sept. 21 community meeting to be held at St. Luke Community Christian Church on budget cuts. NAACP officials said they had not organized the student walkout but supported it.

Contact staff writer Dan Hardy at 215-854-2612, dhardy@phillynews.com, or on Twitter @DanInq.