Families long-frustrated by bus service for students in special education programs have enlisted the advocacy help of Norman Siegel, the former head of the New York Civil Liberties Union, to document -- and possibly rectify -- repeated issues with school bus service.

Over two months this fall, parents reported habitually late pickups; missed instructional time because of bus delays; overly long or nonsensical routes; and poor communication between the Education Department’s Office of Pupil Transportation and bus companies as well as between the Office of Pupil Transportation and parents.

Based on the anecdotes from 38 families, Siegel on Tuesday called for improvements, including creating an independent advocate who would serve as a liaison between families and the Office of Pupil Transportation.

Sara Schiller, whose six-year-old daughter takes the bus from SoHo to a school on the Upper West Side, agreed with the idea of an advocate. She said she experienced repeated bus issues over the summer and fall -- including bus rides more than 100 minutes long and a bus with no air conditioning on extraordinarily hot days -- but did not succeed on her own in changing the situation through calls to the Office of Pupil Transportation.

The system wears parents down, Schiller said.

"As a parent of a disabled child you are already doing so much more," she said. "You are working extra hard on daily living, on working with the school system and managing their disability, managing medical issues. And to have to then, twice a year for tens of hours -- 10, 20, 30, 40 hours -- deal with a bureaucracy and a system that is broken and doesn't actually have a customer-centered or care-centered approach is disheartening."

Siegel said that, when pressed and when presented with repeated documentation of bus mishaps, the Office of Pupil Transportation fixed the problems. He noted that an independent advocate, perhaps a member of the public advocate’s office or of the five borough president’s offices, could play this role permanently.

“The people at O.P.T. in my opinion are not the hostile bureaucrats,” said Siegel. “They did care. But it just didn’t seem that they knew how to make the routes work.”

Still, Siegel said, the repeated issues with school busing are “not inevitable.”

Siegel addressed a letter explaining the findings and recommendations to Mayor Michael Bloomberg and School Chancellor Dennis Walcott. But also copied were mayor-elect Bill de Blasio, public advocate-elect Letitia James and the incoming borough presidents with an eye toward remedying school busing by the start of next school year.

A spokesman for the D.O.E., Marcus Liem, said Tuesday that the D.O.E. was reviewing the letter.

"Earlier this fall we met with Mr. Siegel and several parents to listen to their concerns," said Liem in a written statement. "We have successfully addressed the issues raised, and we are always interested in suggestions to improve our services to students.”

The complaints come nearly a year after a month-long school bus strike last winter, which disproportionately affected students with disabilities.