The same thing happened to my chicks! My grandpa had a hen with 3 chicks and the mother died, so he gave us the 3 chicks, they weren't even a month old. What we did was we would let them be outside (only when I was out, because I didn't want them to escape through any tiny hole), and when it was night time we put them in a cage and took them inside our house. We also put them under a blanket so that they could be warm.
But I don't know if you want to make them grow differently because I wanted to have them follow me everywhere (and they are), but if you have other chickens, you can let them raise the chicks. But whatever you want, let them grow with the chickens or you take care of them.
My chicks are like 4 months now, if there weren't any falcons flying around (which there always are) I would let them roam free, but for now we put them in this big cage that lets them dig in the dirt. I'd let them roam free when they are adults, because I wouldn't want to risk a falcon or eagle eating them.
In the winter, if it is too cold then you'd probably want them to be inside if there isn't a chicken warming them. Also, if you're gonna be the one taking care of them, you should always take them inside whenever you see that the sun is setting.
Oh, and, be careful, because the racoon will be back. A racoon ate one of the chicks one night, it came back the next night because some things were out of place. So make sure that at night wherever you chickens are sleeping, that the door should be really closed shut and not have any places that the racoon could get through.