I liked the Montessori program because he could grow and learn at his own pace. Either way, he could use the social interaction of his age group and older. Do you have any advice? I want to make sure I am helping to grow his gifts -- whatever they may be -- and I know this is a critical age.
You are clearly an observant mom, one who has a keen eye for what your son does and does not need, and what he can and cannot do. If you really believe that the available preschools will not match your son's abilities, see if you can organize other activities for him, especially if they involve older children. Gifted children often benefit from multi-age groups because they can get some of their intellectual needs met by older children and their social needs met by their age peers. By his activities and choices, your son will self-select children of similar abilities.
Perhaps you can post notices in a community center or in houses of worship in your neighborhood to invite families to join playgroups based on common interests. I have even seen such signs in our local grocery store! The kind of situation you describe is actually quite common. There might be more people like yourself in the community than you think.
You also might want to contact the local chapter of an organization for gifted and talented students to see if they have had similar requests. You can find information about these groups either by contacting the person in charge of gifted programs at your state department of education or The National Association for Gifted Children ( nagc.org). Also, college and universities often have special programs for gifted children, including preschoolers. These frequently take place on weekends, after school, or in the summer. You might want to contact the education or child development departments of the university closest to you to see if such a program exists or whether you can help start one. Good luck!