hi!
I have flown a lot with my kiddos and often without DH. I also, as pp mentioned, bring the usual stuff and my kids do well. I bring plenty of snacks and also things that are chewy for takeoff and landing (gum or even fruit snacks and tootsie rolls which I usually prefer that they NOT have). When they were a bit smaller I also purchased a new, small toy for them
(actually 2, one for each way) and didn't give it to them until we were in the air. You know how new toys are....great initially and then forgotten but you only need a couple of hours!
I always, for pratical things, pack wipes/ wet ones and I still pack (well...now we won't be checking luggage as much but when we did) a spare tshirt, pair of underwear and a light pair of pants/shorts for each. Accidents happen be they food, illness or otherwise! Those I pack in gallon sized ziplocks and they take up minimal space but come in super handy. I also usually take a tshirt for myself...incase someone gets sick on me!
Finally a small bit of kids tylenol or something because there is nothing worse than having a kiddo who suddenly has a headache or something and you have nothing for them on the plane ride.