While schools chief Paul Vallas spends this week in New Orleans giving advice on how to rebuild that city's Hurricane Katrina-ravaged schools, students at one Philadelphia school have been evacuated from their crumbling building.

Yesterday and today the 280 5th- through 8th-graders at the Middle Years Alternative School in West Philadelphia had classes at the School of the Future in the Parkside section because of their building's deplorable condition, the Daily News has learned.

The roof of the school, at 4901 Chestnut St., has leaked since the beginning of the academic year, and things only got worse after the heavy rains from last month's Nor'easter, according to Darryl Tate, treasurer of the school's Home and School Association.

"The classrooms on the third floor began to fall apart and a very strong mold-type odor began," he said. "Children have been getting sick and four have been rushed from school to the emergency room at Children's Hospital of Philadelphia."

Among those children was his daughter, who was treated for stomach discomfort, which Tate said he believes was related to the condition of the building.

On Wednesday afternoon, a teacher was injured when part of a ceiling collapsed on her shortly after she sent her students to lunch, Tate said. The teacher was rushed to Lankenau Hospital.

Amy Guerin, a school district spokeswoman, said a piece of plaster had broken loose from the ceiling and hit the teacher. The teacher has since been released from the hospital.

Guerin attributed the damage to rusted ceiling anchors and a water leak. The school is more than 80 years old.

An independent licensed structural engineer and a district environmental expert have inspected the building and determined that it is safe, she said.

And though mold was found on one piece of tile, Guerin said, "there is no visible mold growth elsewhere."

"The school district is going to be working through the weekend to replace all of the anchors on the second and third floors of the building and make repairs to the outside. School will be ready to reopen on Monday," Guerin said.

Tate said he feared the cash-strapped district may attempt to do an inadequate rush job. He said the week after the April storm, a district official told him there was no money to make repairs.

"I would like to see some written proof that they fixed the roof . . . The roof needs to be fixed," he said.

Guerin said the district has money to repair the school. *