Glad you could join the flock! I too would agree that some of your chicks are younger than 4 weeks. At four weeks they should be starting look more feathered out. Do you have them under a heat source as some look like they are not fully feathered yet?
Yes they are in a lg cage in my garage with a heat lamp. I just brought them out side with me today because its 90'. Do you think that's OK or do you think I should leave the two smaller ones in? How old would you think they were?
They will be fine to go out with those temps, wish we were that warm over here!! My guess and don't take this as gospel is that they are about 2-3 weeks old. This is just guess as some birds even of the same breed can feather out at different rates.
I'm sure more greeters will be along soon to offer more opinions on them.