COLUMBUS, Ohio - By federal law passed in 1975, children with intellectual disabilities are supposed to spend as much time as possible in general education classrooms.
But a new study suggests that progress toward that goal has stalled.
Findings showed that over the past 40 years, 55 to 73 percent of students with intellectual disabilities spend most or all of the school day in self-contained classrooms or schools and not with their peers without disabilities.
"Given the legal mandate, it is surprising that such a large proportion of students are consistently placed in restrictive settings," said Matthew Brock, author of the study and assistant professor of special education at The Ohio State University.
The study is the first to look at national trends in education placement for students with intellectual disability - previously called mental retardation - for the entire 40 years since the law was enacted.
"I found historical trends of incremental progress toward less restrictive settings, but no evidence of such progress in recent years," said Brock, who is affiliated with Ohio State's Crane Center for Early Childhood Research and Policy.
The study has been accepted for publication by the American Journal on Intellectual and Developmental Disabilities.
The Individuals with Disabilities Education Improvement Act (as the law is now called) has the aim of educating students with disabilities in what it calls the "least restrictive environment." That means they should be placed in general education classrooms alongside peers without disabilities to the maximum extent appropriate.
Decisions about what is appropriate for each child are made by an Individual Education Program team that includes the child's parents, teachers and others.
Brock used several data sources to determine the proportion of students 6 to 21 years old with intellectual disability who were placed in each federally reported educational environment from 1976 to 2014.
The definitions of placement categories changed several times over the 40 years, so it is impossible to directly compare statistics over the entire time period, Brock said. But some general trends can be detected.
He found that in the first years following passage of the law, the proportion of students in less restrictive settings actually decreased. Students served in regular general education classrooms decreased from 38 percent in 1976 to 30 percent in 1983.
From 1984 to 1989 an overall trend is less clear.
From 1990 to 2014, the proportion of students in less restrictive placements initially increased and then plateaued, Brock said.
The proportion of students who spent at least 80 percent of the school day in general education classrooms trended up to near 14 percent in 1998, dropped to 11 percent in 2002, hit a peak of 18 percent in 2010 and decreased slightly to 17 percent in 2014.
"Overall, the most rapid progress toward inclusive placements was in the 1990s, with more gradual progress in the 2000s and a plateau between 2010 and 2014," Brock said.
He believes the rapid progress in the 90s occurred because advocacy for special education was strongest during this period, at least on a national level.
"There are still people working really hard toward the goal of inclusion in some parts of the country, but that doesn't come through in this national data," he said.
One argument could be that inclusion has plateaued in the United States because nearly all students are already in the least restrictive environments possible, as decided by their Individual Education Program teams, Brock said.
But state-by-state data suggests something else must be going on. In 2014, students with intellectual disabilities in Iowa were 13.5 times more likely to spend most of the school day in a general education setting compared to students in the bordering state of Illinois.
These huge discrepancies in placements between states can't be explained by differences in the students. The issue is that states and even individual school districts follow different policies and ways of working with student with disabilities - and not all succeed at giving students the least restrictive environment, according to Brock.
"I don't want to send the message that all kids with intellectual disabilities should spend 100 percent of their time in general education classrooms," he said.
"But I think we need to find opportunities for all kids to spend some time with peers who don't have disabilities if we are going to follow the spirit and letter of the law."