Are you ready for your BYC education?
Okay, doe rabbits are KNOWN for not making good pets.
They are territorial, more than males, so they do not like their space (cage) invaded. What you're seeing (the growling, and lunging), which I am going to guess is when they approach her or go into her cage to get her, is her clearly saying "THIS IS MY HOUSE GET OUT!"
I have a doe right now who is like this and a young doe who I know is going to be like this. Typically, once you get these rabbits out of their cages they are fine.
Another thing to keep in mind is that rabbits are Prey Animals. Literally EVERYTHING like rabbit dinner, and they have little in the way of self defense. Their main defense is their speed in getting away, and a strong kick of their back feet which with sharp nails can really gash a person open.
Those things being said, rabbits aren't the best pets for kids IN MY OPINION. They are not like kittens and puppies, the majority of the population of domestic rabbit DO NOT enjoy being held and loved on.
There are always exceptions to this rule. You will always hear someone say that so and so had an awesome pet rabbit that loved being held and so on and so forth...
These rabbits ARE THE EXCEPTION AND NOT THE RULE.
These rabbits are generally rabbits that were handled tons from the time they were very little babies.
I have one myself. Her mother is a jerk, her father is nippy, but she was a single kit litter and was handled tons from the day she was born and I can do anything to this rabbit, turn her upside down, scratch her tummy, she will practically jump into your arms when you open the cage door. It took alot of work to get her like that, it did not happen on it's own and it's HIGHLY unlikely that a free feedstore rabbit will be this friendly.
At this point the only thing you can do is let her know you're the boss. Do not show her that if she puts up a fuss people will leave her alone. Hold her anyway, offer her treats, etc. But come to grips right now with the fact that this particular rabbit may never be a great loving pet, especially for kids.
My advice to you would be to see if she comes around for a month or so and if she doesn't sell her on your local craigslist (may seem harsh but if you have young kids you don't want them to have a bad experience with rabbits) and buy a baby bunny (a male!) from a small hobby breeder who has likely handled the kits from a very young age OR go through a local rabbit rescue who specializes in spaying/neutering and litter box training the rabbits...
Or just go with a kitten instead