Hundreds of students with disabilities across the country, if not more, are illegally being kept out of school without access to special education services due to their behaviors, advocates say.

A report out this week from the National Disability Rights Network highlights several kids who have experienced what the group is calling “informal removal.”

The off-the-books suspensions come in many forms, according to the network, an umbrella group for the federally mandated protection and advocacy organizations in each state. Some students are repeatedly sent home from school while others are limited to shorter school days, assigned to homebound placement with minimal education or remote learning, the report says. In other cases, school districts transfer students involuntarily to programs that do not exist, have no openings or ones which the child does not qualify for.

“The reality is that we have no idea exactly how many children are removed from school each year because school districts do not include informal removals in reports to the public,” said Curt Decker, executive director of the National Disability Rights Network. “But we do know that our network represents hundreds of such children per year and that these removals hurt them.”

The report tells of a 6-year-old with complex medical needs who was only allowed to go to school one day a week. Another child with autism was placed in homebound services in second grade because of his behaviors and did not have a seat in a classroom for at least three years. And, at one school district, three kids with autism were routinely sent home because there were too few paraprofessionals and the children were deemed “too hard to handle.” One of the students was kept out of school for nearly a year.

All of this is occurring despite requirements in federal law that children with disabilities receive the behavioral services they need so that they can be educated alongside their peers to the maximum extent that’s appropriate, the report notes.

Informal removal is so pervasive in some places that school staff don’t realize it’s illegal, the report found.

The National Disability Rights Network is urging the U.S. Department of Education to issue guidance clarifying that all students should be attending school for the full day and receiving a full day of services. In addition, the group said that the Education Department and the Department of Justice should increase enforcement and federal and state governments should ensure that schools have the resources they need to properly address behavior issues.

“Informal removal and lost instructional time have long-term negative economic, health and community impacts for individual children and their families,” said Diane Smith Howard, managing attorney at the National Disability Rights Network and the primary author of the report. “Federal, state and local officials must take action to stop the practice of informal removal.”

Aryele N. Bradford, a spokeswoman for the Justice Department, pointed to a settlement last year with a Maine school district to address shortened school days and another one with a Maryland school district regarding the use of restraint and seclusion. She did not comment on whether the agency would be pursuing more of these types of cases.

The Education Department did not respond to a request for comment.