I let my hens brood their chicks in with the flock. They do fiercely protect them if the others get too nosy. If weather conditions are right they take them out and free range with them during the day, otherwise they feed and play in the coop. The only problem I've had is that in the first few weeks of the hen taking the chicks outside, we've had to help them find their way up the ramp and back in (our coop in a few feet off the ground and the hens tend to fly up to the pop door). After a few times of this they catch on and its smooth sailing from there. The only predator we've had take out a few chicks are the hawks, otherwise the dogs keep all others at bay.
Good luck and have fun, its great to see a hen hatch and raise a brood of chicks...and so much easier than trying to do it yourself!
Also, until the chicks start to go outside, I keep a feeder of starter/grower on the floor of the coop along with waterer set in a pan (to keep it as clean as possible). I hang the layer food for the older chickens so the chicks can't get at it until they can fly a bit, and by then they are going outside and are eating a variety of food and grit from foraging.
