My 2 year old son goes to Whitelodge at Eastgate and it's fairly mixed but there is a weight towards more Australian, American and British children, then the rest are either local Singaporean, chinese, malay, indian, Turkish etc. I couldn't really say whether it's classed a local or
International School though.
There are so many pre-schools to choose from it blows your mind, but I would recommend finding somewhere close to where you live, unless you will be getting a car. The fees can vary dramatically too, so it's not until you get here when you start looking around them all that you get a feel for what you like and don't like. I saw about 6 different schools, mainly local actually as they are closer to where I live, before deciding on Whitelodge.