I have just booked a 5th birthday party at Bunnings! That's right Bunnings. They do a craft activity, face paint, play in playground, some party games and have a party coordinator and then all you have to do as a parent is bring some simple non heating party food and a birthday cake. It goes for 1 1/2 - 2 hours. And it costs.....$0! So maybe worth checking out if your local store does them.