Fairly good choice of international schools on Samui (No sixth form to speak of though) and even more in Phuket of course. However we often holidayed at Birds and Bees resort (unreal place for kids) in Pattaya in half terms as there was so much to do and many attractions for young kids in and around Patts........Samui had a real nice friendly vibe at the schools IMO, even had inter school swimming galas.This was in the noughties BTW.................However if you ever want to consider a non beach city for a really great all round education experience and lifestyle, you can't beat Chiang Mai IMO. A fantastic choice of decent international schools there. Either way, you'll have great fun bringing up a young child in their early years in Thailand................................