You can bring food (snacks, sandwiches, etc) through security, but not liquids like bottled water or sodas. However, you CAN bring an empty water bottle and fill it AFTER you go through security. I usually take an empty water bottle and fill it after security, so I don't have to purchase the over priced meals in the airport.
If you can, bring a tablet with videos or games on it and headphones. That will be a great thing to help keep kids occupied. You can even get 2 person games that your kids can play with each other. If you can, find a place to recharge it on your layover. With only an hour layover, you will not be able to fully charge it, but any little bit will help.
Bring gum for the kids to chew on take-off and landing. That helps make them swallow, which helps ease the pressure on the eardrums. Adults usually know how to equalize the pressure in their ears, but most kids don't know how and it can get painful.
Even though your daughter is very talkative, she has to be quiet in school... just remind her that she needs to use her inside voice to keep from bothering other passengers.