Children on the autism spectrum face challenges with communication, social interaction, sensory processing, and repetitive behaviors. According to a study from 2014, nearly a third also have an intellectual disability. Every diagnosis is an opportunity to help a student who might otherwise struggle.

Unfortunately, our growing understanding of autism in the medical community has not yet translated to U.S. school systems. Educational strategies to help students with ASD have remained largely unchanged for decades. Without significant improvements in policy and practice, an entire generation of children may lose the opportunity to become independent, productive members of society.

The good news is that we know what–and who–can help. As a professor of occupational therapy at New York Institute of Technology, I have more than 20 years of experience training healthcare professionals to work with students on the autism spectrum. I’ve seen how occupational therapy can help children with ASD improve their communication skills and I’ve seen the impact of physical activity on brain function. I’ve seen the kinds of interventions that work–and those that don’t.

While most children with ASD receive early intervention during their preschool years, the services change once a student enters the K-12 system. In general, students with ASD are placed in special education classes, separate from their neurotypical peers. There, they receive “free and appropriate” educational services, as required by law. However, teachers can’t always access the training and resources they need to tailor education for students with autism, and due to these students’ challenges in motor processing, they are often excluded from sports, music, and other extracurricular activities.

This model woefully marginalizes children with ASD.

Occupational therapists and other healthcare professionals who specialize in helping kids with autism can play a vital role in supporting these students. Their training allows them to assess schoolchildren and design targeted interventions. Yet most schools don’t have the resources to employ such specialists.

Among those that do have resources, some have tried to hire out these roles to independent contractors, but this doesn’t work over the long run. While well-intentioned and often talented, non-unionized workers who are not on staff don’t become part of a child’s educational team. They find it difficult to advocate effectively for their students and provide consistent, ongoing therapy.

This is where policymakers must step in. We need changes at the state and federal levels to ensure that appropriate ASD intervention continues beyond preschool. K-12 schools should be required to have occupational therapists or other autism specialists on staff.

We also need policies that support equitable resource allocation across public schools. Families of means can often access effective ASD intervention outside of school, but in-school programs and specialists are essential to making sure that children of all backgrounds get help.

Finally, we need to make sure, as a matter of policy, that children with ASD have opportunities to engage in sports and are encouraged to move frequently during the school day. Too many schools have eliminated recess and physical education in favor of more rigorous academics. This is bad for all children but disproportionately harms those with autism, whose cognitive and physical development greatly benefits from exercise and play.

In my own practice, I’ve seen significant neurological and cognitive improvements when exercise and play are prioritized. One student, for example, joined a running program at school. At the time, he was enrolled in special education classes. Running boosted his confidence, social abilities, and language skills. He started attending regular general education classes with his neurotypical peers and became an honors student.

This kind of radical improvement may still be relatively unusual, but it doesn’t have to be. A shift in policy and priorities can ensure that all students with ASD get the interventions they need to thrive. With effective therapies delivered by trained healthcare specialists, children with autism can become less marginalized, more independent, and participate meaningfully in everyday life.

Alexander Lopez is an associate professor of occupational therapy at New York Institute of Technology.

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