DES MOINES, Iowa �?After failing to finish a reading assignment, 8-year-old Isabel Loeffler was sent to the school's time-out room �?a converted storage area under a staircase �?where she was left alone for three hours. The autistic Iowa girl wet herself before she was finally allowed to leave. Appalled, her parents removed her from the school district and filed a lawsuit.

Some educators say time-out rooms are being used with increased frequency to discipline children with behavioral disorders. And the time outs are probably doing more harm than good, they add.

"It really is a form of abuse," said Ken Merrell, head of the Department for Special Education and Clinical Sciences at the University of Oregon. "It's going to do nothing to change the behavior. You're using it as an isolation booth."

Segregating children removes them from the positive aspect of the classroom and highlights that they're different from other children, said Stephen Camarata, director of the Kennedy Center for Behavioral Research at Vanderbilt University. And isolating an autistic child might be particularly counterproductive.

"They don't like being around other people so they might increase their negative behavior because they view it a reward," he said.

Though there is no data on the use of time-out rooms, Camarata speculates that they've become widespread as schools confronted a growing enrollment of children with behavior disorders.

"I believe it's because classrooms are much less flexible with more focus on compliance," he said.

The Disability Rights Education and Defense Fund in Berkeley, Calif., receives calls from parents across the country who complain about time-out rooms, said Cheryl Theis, an education advocate for the organization.

"Parents call and say their child's disability has been exacerbated by this and are traumatized by this," she said.

Merrell said he's encountered time-out rooms he felt were unsafe.

"I once consulted with a school in another state and had a weekly appointment with a child to do some counseling and when I got there they told me he was in a time-out room," he said. "He was in a janitor's closet with no windows, no ventilation, open cans of paint, a mop bucket with disinfectant and he had been in there for over an hour."

Merrell, who has published nearly 100 studies and 10 books on teaching social and emotional skills, said time-out rooms can be used effectively but seldom are. The key, he said, is to combine the time outs with social skills training.

Patti Ralabate, a special education analyst with the National Education Association, said time-out rooms are common but should be used sparingly.

"And when they are used, all of the educators involved need to have appropriate professional development to see how this is used and how to use them appropriately," she said.

Ralabate said a time-out room can be effective if it is intended to provide a space for a child to calm down and reflect on their behavior.

"If it is used to isolate the child, punish the child for a behavior, then we would view it as not productive and not positive," she said.

In Iowa, Doug and Eva Loeffler started to notice changes in their daughter in December 2004, soon after she began school in the Des Moines suburb of Waukee. It prompted them to take Isabel to University Hospitals and Clinics in Iowa City for evaluations.

"We laid awake at nights thinking we'd have to institutionalize her," Doug Loeffler said. "We went to three evaluations at the hospital and all of a sudden we find out she's being mistreated."

Loeffler said they weren't told in school evaluation reports that their daughter had been restrained and placed in a time-out room. During one incident in December 2005, Isabel wet herself because she was locked in the room for three hours and not allowed to use a restroom, he said.

Loeffler said the time-out room rules required that before she could be released, she must sit on the floor with her legs crossed without moving a muscle for at least five minutes.

"If she said something, grimaced at them, they would restart the clock and she was not capable of doing that," Loeffler said. "That's why it was three hours."

Loeffler said the couple homeschooled Isabel until he took a new job and the family moved last year to California. Isabel has shown signs of progress and is back in public school, he said.

David Wilkerson, superintendent of the Waukee school district, declined to speak about the accusations because of the pending lawsuit. But he said time-out rooms are a "pretty common practice" and that the district complies with the state's guidelines for such rooms.

Loeffler said he is pressing ahead with the lawsuit and hopes to draw attention to the need for nationwide standards for time-out rooms.