We did this last year, and it worked fantastically

, my DH & I booked almost 12mths in advance to take our 2 DD's along with my parents, we told our DD's that we would be going on holiday but we hadn't booked anywhere at the moment, I bought all the essentials, had the cases packed without them noticing

, bought them lanyards and pins of ebay

, We booked our taxi and told the girls we we're all going to a water park for the day

, I helped them pack their bags (hand luggage

) they didn't question anything as they had their goggles in their bags, my DH took our luggage to my parents the night before so they didn't see it, and even when the taxi came the next morning even the driver played along with the trip of going to the water park!, Our DD's were as good as gold colouring in the taxi, and as we're approaching departures at Manchester Airport our eldest DD questions the airport

what are we doing here??, where are we going, it was wonderful they we're soooo excited

. Keep it a secret it's soo worth it.