Chick(s) are losing feathers, not sure if it's normal..

So a little bit of background first so I give all the information I can. I've got 6 chicks, around 5 weeks. I was told they were all pullets but I'm about 80% sure I've got one cockerel. They are just now starting to finish getting their breast feathers. I do believe they are Australorps but I am not 100% sure, I was told they were barred rocks when I bought them. I keep them in my garage which stays around 70 degrees or so. I have them in a roughly 6ft X 6ft area in my garage with pine bedding on the floor. They are on organic chicken starter, I also supply grit. I give them treats once a day usually either a treat mix or superworms. Now I totally cleaned out their cage today and noticed when sweeping up there was a bit of feathers around the pen with the bedding. Not a whole ton but enough that I noticed. I checked all the chicks and none seem to have bald spots apart from the patchiness where their feathers are coming in. I wasn't sure if this was normal or should I be concerned? If it's not normal then what could be the cause and how would I fix it?

Young chickens of that age usually go through a mini "juvenile molt." This is when the first stage feathers are being replaced by the second stage feathers, and the cockerels start to grow in their showy "rooster feathers." As long as your chicks appear to be healthy, and none of them appear to have been picked on by their flockmates, you shouldn't have to worry.