Entertainment on an airplane?

Hello! Me, my husband and my almost 9 month old baby boy are flying on an airplane from CA to OK on Friday and I have flown with my son by myself a few times already in the past, but the last time he was only four months old and the other times he was 2 months, so those were quite easy as he slept the whole time!! Now he is a very very very active little boy climbing, crawling and getting into everything, as most babies his age are!! My concern is that my son is the pickest sleeper of any kid i've ever seen!! He hardly will even sleep in the car and most kids p out the second they hit the carseat!! No, not him!! He has to have HIS bed and he barely even lets me rock him to sleep so I just KNOW he will not sleep on the plane or at the airport either, so not only is he going to be active but he will be very tired as well!! I need some advice on things to do to keep him entertained, luckily we have a layover so i can let him stretch and crawl around on the layover! I have some toys packed and of course pacifiers but I was wondering if there was anything else I could try? Thanks so much!