I need some tips to keep them busy. I have a few new toys I am bringing, along with snacks and blankies/nuks. I am just at a loss of how to keep them entertained. Despite my best efforts they do not watch TV lol, I have tried to get the interested and they just don't care. Any advice would be greatly appreciated

TTC since 2005
missed miscarriage nov 2006- 4 failed clomid cycles-
3 failed femara iui cycles-
moving on to IVF oct 2011
ER nov. 7th
tansfered 2 blasts on 11/10
lots of +hpt!!
beta #1 on 11/21= 50.4
beta #2 on11/23= 90.8
another miscarriage 12/23
moving on to Round 2 of IVF with an auto immune dx
ER 4/23-retrieved 12 eggs
ET 4/28 3 transfered
Beta #1- 356
Beta #2- 870

Re: Flying with 20 month old twins
I picked up the "magic" coloring book that comes with the marker that colors in all the colors on the page when scribbled. That seemed to provide a lot of entertainment for DD who was 21 months old at the time.
There was also the leap frog learning laptop, which worked also.
Most importantly, do not forget snacks and enough diapers for a week!
Just flew alone with my 17 month old. 4 planes (luckily short flights of 1 and 2hrs each).
Key survival items were buckles. My daughter is obsessed with buckles so I let her play with the buckles on the baby carrier that I wore her through the airport with. She spent a lot of time doing the buckles.
Stickers. A good 20 min of sticker time on 2 flights. I bought the mess free markers, Crayola brand that only work on the special paper. She wasn't in the mood for colouring (yours are older so might be) but she LOVED putting the markers in and out of the box. Tip though 2-3 markers is plenty the more you bring the more they want and the more to roll away!
New books worked wonders. My daughter has zero interest in tv but I did have it on and it caught her attention for a couple seconds here and there...which can help ward off a melt down so why not!
And snacks. My daughter is a great eater, eats anything and everything. She does not eat much 'junk food' but I loaded up on those fruit gummy snacks (I got the ones that had at least some real fruit juice). These kept her busy during the hardest part of the flights (taxi-ing where you are barely moving and there is no noise- I find once in the air the plane noise lulls them calmer). I also allowed apple juice when the flight attendants serve drinks, she normally rarely has any juice so it is exciting.
My daughter has flown on about 20 flights now...she is a great traveller the only hard part is having her immobile...she is very busy. So it takes a lot of distractions to keep her occupied. Just have tricks up your sleeves. I sang wheels on the bus so many times last flight because there was a bus on her book and she loves the song. She only wanted to hear the wheels and the mommy part (her favorite action ones). Luckily the noise of the plane drowns out your voice so the neighboring people don't really hear you singing quietly!
Oh DO NOT do pre-boarding...that is just a mean trick to make parents work even harder on a flight. We board last, very, very last. Last thing a toddler needs is an extra 20-30minutes of being forced to stay still. I also find when the plane is full upon boarding my daughter is distracted by all the people we pass and is a bit more timid once in her seat then she is if she enters an empty plane and wants to climb all over. That's her personality though, timid for a bit then chatty and playful.
I didn't try with my daughter but you can bring some big lollipops on the plane. keeps them busy and quiet :-)