If you've ever wanted to pack your kids warm lunches, but aren't sure what containers work well, I've got two recommendations below. Being able to pack room temp finger foods AND warm lunches has given me a lot more options when packing my kids' lunches. Anytime we've got leftover pasta, fried rice, chicken noodle soup, etc. - it's one less lunch I have to prepare. I also have more options to make fast lunches that taste much better warm, like scrambled eggs or quesadillas. And want to keep the lunch cold, like yogurt topped with fruit and granola? Works great for that too.
Older kids, ages 5+: Thermos foogo food jar
The thermos foogo food jar has a twist top, and does an excellent job of keeping lunches warm. I recommend this one for older kids because younger kids have a harder time with twisting off the top themselves (which I realized when co-oping in my son's pre-school class).
Younger kids, ages 2-4: Think food container
The think food container is one that younger kids can open and close by themselves. It doesn't keep lunches as warm (or cold) for as long as the thermos foogo food jar does, but it's good enough. I've learned from my son's preschool teachers the importance of young kids developing good eating habits early on - and part of that puzzle is giving kids lunches they can open and close themselves. For those of us with toddlers, I'm sure you've witnessed the intense desire to be independent via "I want to do it myself!!!" rampages. Well, your toddler will be satisfied with being able to lift and close the flaps on the lid of this container - thus one step closer to fostering independent eating.