sticker books, etch a sketch, nothing droppable like crisps/ crayons/ small toys. Try to find magnetic playboards (you know, set a scene with dora stuff) and pack them each a small bag with: change of t-shirt, pkt sweets/raisins, toy, nappies, wet wipes. If all else fails, walk the baby repeatedly up the aisle in your arms and let people smile at him/her. 9 times out of ten they do. Then try medised..
I recently had a great success with Baby in a Bag from ELC. Little soft bag with small soft baby, hat, babygro to pull on and off, teddy, blanket and bottle to feed baby. DD 18 months loved it. Only a shortish flight but she played with it and then spent a much longer time walking up and down the aisle with it. I like Milky bar buttons for take off and landing when they have to be completely restrained.
Children's mags bought from airport - can carry them on extra to handluggage, they often come with little free toys that DCs haven't seen before and you can read to them. When the boredome really sets in they can rip them up
If they'll still take a dummy (assuming they ever had one) - pop 'em in for take off and landing - easier than sweets, drinks etc to stop their ears popping.
fantastic, great ideas thanks. yes will definityl be taking a dummy for the youngest, i'm dreading them getting ear ache. actually i'm dreading the whole flight so i'm impressed with your suggestions, hadn't thought aout sticker books etc, plus we have seatback tv screens so that should occupy them for a little while