Gifted Issues Discussion homepage Forums Learning Environments How can I know that which school is the best fit?

You write that he hasn't started speaking English yet.
Unless he will be in a school that is familiar with kids speaking English as a second language, I'd make sure he has good language skills on entry so he can *show* how bright he is, rather that the teachers having to take your word for it until he is fluent. If he enters kindergarten without good English skills, they may give him even lower level work which may bore and frustrate him even more than the regular curriculum.
To that end, I'd look at preschools in your area. For a good fit, I'd look for play based or Montessori schools (NOT academically focused schools, which would only bore and frustrate him too, just earlier than elementary school would) with a nurturing environment and small, preferably mixed age classes. (I'd also look for a strong outdoor component to the program, but that's me).
Trying to teach him English at home it's not the same thing - it's best for his bilingual development if he speaks your native language with you at home and learns English from native English speakers in a distinct environment such as preschool. Learning English is also going to keep his wheels churning, a good thing for any gifted kid.