As a previous Early Childhood Psychologist for the North Shore, I have several suggestions. First, be sure to contact NSSED, Northern Suburban Special Education District
760 Red Oak Lane, Highland Park, IL 60035 ###-###-####. Your son may be eligible for the free program offered through your school district. If he did not received an educational assessment at age three, this can occur through their services. They can also assist you with a referral to private preschools with whom their students have had success.
If you wish to discuss elementary schools which are known for providing the best services in Glenview/Northbrook, I can be reached at ____@____.com.