Personally, I would never get a rabbit for a little kid (under age 12/13). They are too fragile for rough little kids. My princess Peanut was previously owned by little kids (under the age of 13) and she was given to the humane society because she bit everything and anything that was stuck into her cage, including fingers. I don't blame her one bit, I would do the same thing too. I know she was not well taken care of, it was extremely evident based on the stupid commets they left on her papers. Since I have adopted her she has never bitten me once. Rabbits break their bones quite easily, if someone doesn't handle them properly it doesn't take much for them to break their backs or leg bones. Also, they need a lot of attention, and like 90% of kids they will be crazy over the pet for a while then get bored with it over time and it soon becomes the parents' job to care for the animal- rabbits need a dedicated owner that will give it what it needs when it needs it. Of course, this may not apply to your kids- this is for some kids in general, it's very common. That is just my personal viewpoint on (younger) kids and pets.

Peanut is a large breed, she is an American Chinchilla and weighs in just a little under 7 pounds. Buster is a Dutch and is a little over 4 pounds. If you are 105% sure that you're kids are up for the challenge of rabbit ownership, then follow WolfChan's advice and look into a large breed- they will be heartier compared to a Netherland Dwarf or similiar small breed. Good luck with your bunny search, show us pictures of the rabbit when you get one, or ones you are interested in!!