Best suburbs with great private schools to live while working in NYC

Hi, my husband was offered a job in NY. We have an 11 year old that goes to private school. Where is the best/safe suburb to live in that has good private schools? We have been many times to Manhattan on vacation but never visited the suburbs. We are Canadian expats in Puerto Rico.
Any suggestion would be very helpful.

What do you consider a suburb?

HaileyinHongKong wrote:

What do you consider a suburb?


New Jersey?

She said "best/safe".  That rules out New Jersey.