Hi HH Welcome..
Don't know if this will be of any use to you but another couple moved over to Crete earlier this year, they have a 12 year old daughter who speaks very little Greek (she started taking some classes in the UK) Anyhow, she has been enrolled in a school in Vamos. Her parents seemed really pleased with it, don't know all the info, I don't have any young children so never got into all the details.
WHich part of Ireland are you from? I know a few people from Dublin.
we are moving out to Crete, infact we expected to be there in Aug/Sep this year but due to circumstances... the sale fell through on our property but as soon as we sell the house here, we'll be off , we have a property in Kournas which isn't too far from where your going. Good luck with your move, email me if there's anything I can help you with