Having recently travelled between Canada and India, with two toddlers, here's seven my tips to keep your kids entertained (and yourselves sane) during long haul flights.
1. Travel as light as possible
This is a general advice, but particularly suitable for travelling with kids. Just because you get two suitcases per person, doesn't mean you need to take two suitcases per person.
Remember, one parent will be taking care of the kids. The other parent will be taking care of the luggage. If you have ten suitcases, good luck. Our rule for four people was that we would take two suitcases full of our clothes etc. to India, and also carry two additional suitcases (empty) to bring stuff back. Everything (and that includes hand luggage, strollers etc.) should fit on two trolleys. We basically took half our quota and it made life so much easier.
2. Check everything in
When you have a screaming baby upset at something or the other, with the older brother angry because the younger one has taken his toy, and you are trying to go through security and taking your belt and shoes off, you don't want to deal with three carry-ons and two backpacks. Whatever you can, check it in. Obviously this is easier if you have less luggage over all to begin with (see #1).
3. Make sure to have extra set of clothes on you in the cabin
This would be in the backpack or carryon you took on board. There should be one extra set of clothes for everyone. For kids and for yourself as kids can pee on you (don't ask).
4. Dollar store sticker books are your friend
We took lots of activity books such as sticker books and colouring books that we bought from the dollar store. Kept the kids engaged for hours and you can throw way the book when done. We also took a few of their favourite toys, as well as loaded up the tablet with their favourite movies and TV shows. Bottom line: you have to keep your kids busy.
5. Bassinet seats are great
Try to get the bassinet seats (I called up Emirates to book seats on phone) even if you don't need the bassinet, as you still get the extra leg space. This is particularly useful if one of your children is under the age of two and doesn't have a seat of their own.
6. Snacks and Biscuits are meals too
Children usually don't like plane food (heck some adults don't either, and I don't blame them if it's Air Canada). So even if you ordered the special child meal, don't be upset if your child takes a bite or two and then proclaims "I'm done". Have lots of snacks, crackers, chocolates, Kinder Surprise etc. whatever junk foods the kids love. A Kinder Surprise (or called Kinder Joy in India) has the additional bonus of also being a toy. #keepthembusy
Remember, despite all of your best efforts, there will be a time they will cry and shout. Don't worry about it and don't worry about what anyone else things. Just try and tell yourselves "five more hours" and relax.