My first thought is Montessori school, that is a private school that teaches kids at thier own pace. There are two up near me, in Downingtown/exton. You could probably do some more research and find other options. It's also something you could do for a couple of years and then re-integrate your son back into public if you so chose. I will list two in the area at the bottom.
A second choice in this area if you can afford it is the Friends school. They are quite popular but very expensive.
If you are looking for something very different, you could also try a waldorf school. There is one in Glenmoore. They
are more wholistic. They do not teach in a rote method. They nurture the whole child, using music and creativity.
I have also been told that there is a charter school in Glenmoore. I have not looked into it. They are said to be very "technical" It was suggested to me as I have a 4 year old son with a summer birthday who has a facination with electricity. I need to make some decisions this summer about which direction to go.
My son is currently is enrolled at the Chester County Early Intervetnion program (and hopewell preschool) and is receiving speech, OT and PT. He is very unique (imaginative) and I have a lot of concerns about putting him in kindergarten next year. Fortunately Downingtown schools offer a K-1 class for kids who have late birthdays and might not be ready, they have an option to do 1st grade twice.
West Chester does also offer lots of great services through the Chester County Intermediate Unit. But as your son is already enrolled in Kindergarten he would not qualify for Early intervention. He might qualify for other services. All of which is paid for by the state,
I hope this helps. Below are the two Montessori schools that I could find in the area. I am listing these as they seemed to be the closest to what you are looking for.
Children's House Of Lionville
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www.montessori.org/
Whiteland Montessori School
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