Jessie, that's exactly what I have been doing in CO for the last two weeks. I sectioned off a 3' X 3' area of my coop, made a brooder with the top and one side covered in plain old chicken wire, the other sides in solid sheathing, hung a heat lamp and put in a waterer and feeder for the chicks. Nothing fancy, even the measurements on the sides are not exact. Pine shavings on the floor and a piece of 2 X 4 with the 2" side up just laid on the floor for a somewhat elevated roost. Our temps here at night have been as low as zero but averaging in the low 20's, and during the day have ranged from about 30 to tomorrows beautiful predicted 68. At night I cover the 3 X 3 brooder with a piece of solid sheathing to retain heat.
I have it easy in that this is a new coop with no other current occupants, but I believe this setup would work even if I had other, older birds, and would also allow them to become familiar with each other before I released them into the existing population. In fact, as I have two more batches of chicks coming in over the next 3 weeks, that is exactly what will happen. The older chicks will be released into the main, open part of the coop while the new chicks will go into the brooder.
Good luck with your chicks.