American law requires a "free and appropriate education" for children with special needs, in the "least restrictive environment". In a litigious society, this wording has helped to turn special needs education into a bonanza for lawyers.
Two issues have proved a political and legal minefield. The first, predictably, is how far disabled children should be integrated into mainstream classes. The second is the huge number of children now classed as "learning disabled" without an obvious mental or physical impairment.
More than five million children in the US, about 10 per cent of the public school population of 44 million, are officially diagnosed as having disabilities. Of this huge number, about half, or 2.6 million children, are "learning disabled". About half a million suffer "severe emotional disturbance", a million or more from speech or language impairment, and a further 500,000 have "mental retardation". The remainder suffer serious disabilities, from autism to brain injury and blindness.
The US spends about $32 billion (Pounds 20m) a year on their education. While the federal government lays down the ground rules, the individual states provide the lion's share of funding. There are many complaints that despite good intentions the programmes have never been funded properly.
The major piece of legislation in the area, the Individuals with Disabilities Education (IDE) Act, was redrafted this year after a political battle. It pitted advocates for the disabled pressing for greater access against conservatives citing costs, and teachers worried about disrupted classes.
Nearly three-quarters of all children with disabilities are taught in mainstream classes for part of the day, it is reported, though only about a third spend more than 80 per cent of their time in such classes.
US policy has rested on the "continuum of placements". After the child is evaluated by a team that typically consists of a psychologist, a social worker, a teacher and a doctor, options run from a regular class through resource rooms, separate classrooms, special education centres, residential institutions, and hospitalisation.
While states typically have separate schools for blind, deaf, and severely emotionally impaired children, policies on admissions vary. States regularly face lawsuits from parents either determined that their children stay in the mainstream or demanding greater resources, and courts have jumped both ways. School districts have sometimes been accused of integrating disabled children to save money.
In the rewriting of the IDE Act, some concessions were made to teachers. "Stay put" provisions meant a disabled child stayed in a class while his or her placement was challenged in the courts. That rule has been relaxed where a pupil is found in possession of weapons or drugs.
The "learning disabled" issue remains controversial. The numbers of children diagnosed this way, with everything from dyslexia to attention deficit disorder, has gone from 800,000 in 1977 to 2.6 million today. Critics say that the label is now applied to lazy, below-average, or poorly-motivated children with pushy parents or schools seeking more state funding.
The argument also is beginning to be heard that the huge growth in dyslexia and other problems associated with poor reading may be laid partly at the door of "whole-language learning". This reading method was adopted in American schools as an alternative to phonics, but is now widely criticised.