Yes discovery bay is a great community. 20mn ferry ride into the city.
You have to be prepared to have your eldest accepted in a school off DB and on the ferry & bus to/back from school. But don't worry he will be one of many.
Clearwater bay & sai kung are great options too with lots of school options as many of the international school are phased to move into new campuses that side of HK.
On Hong kong island, happy valley/tai hang is great to be walking distance to shops. Great balance between local grocers and artisan french delis. Excellent transport, 10mn to work by tram/bus/taxi etc...& only 10mn drive onto the beaches of southside.
On the beach, try shouson hill, repulse bay, stanley. More expensive and taxi/car/bus only. 15-40mn into central.
2 goid tools:
hong kong homes
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squarefoot
You should the FB group hong kong moms. It works like instant messaging!!! There's always someone to give you specific info on anything!
Really, you need to start looking fir pre-scools and bear in mind that your eldest will be elligible for the common Y1 entrance 2015 at ESF. You must apply strictly in september BUT as far as i know you need an address as they operate by catchment. You should call email to ask about late registration for relocations from overseas.
Also, just to add, if you eant to stick strictly to the british curriculum schools, places trilly are scarce with established waitlists.
Don't drop the ball on this it really is a priority.