Thirty years ago, it was rare to find a student with autism in a public school. When children with severe, unexplained behavioral problems turned up, teachers had little guidance in how to work with them. Many experts assumed these children were retarded. Others even recommended physical punishment to curb disruptive or antisocial behaviors.

Today, about one in 150 American children has been diagnosed with autism spectrum disorder (ASD). No one fully understands why the incidence of autism has increased so dramatically. As its name implies, this complex neurobiological disorder is defined by a variety of symptoms, sometimes subtle, sometimes obvious. Children with ASD can be highly gifted but may have speech and learning difficulties. They may demonstrate repetitive or disruptive behaviors like banging or biting. They may have little interest in making friends or interacting with peers, teachers, or even family members.

There is no cure for autism, yet early intervention beginning as soon as the condition is diagnosed and continuing into elementary school can sometimes lead to remarkable success. “We used to hear, ‘There’s nothing we can do,’” says Ilene Schwartz, professor of education at the University of Washington in Seattle. “Now we hear things like, ‘Where’s this kid going to college?’ Because we now know that huge changes can be made.”

At the same time educators are discovering ways to help children with ASD reach their full potential, school districts are coping with unprecedented growth in the number of children with autism seeking services under IDEA—a number that rose more than 500 percent over the last 10 years. The intensive services required by many children with ASD and the need for early intervention place new logistical and financial demands on schools. Many districts are also searching for ways to educate children with autism in settings close to home and in the company of their nonautistic peers.