Growing up so fast!

[chicks370]

I am new to this but so far so good and we are loving every moment of watching them grow! My Australorp and Barred rock are 10 days old and my RIR is 17 days old. They are growing quickly and not sure when or if I should move them to a bigger brooder or if they will be fine until I put them out in the coop in a couple weeks when they are completely feathered? During the day I put them outside (supervised) for about 30 mins since it is in the 80s here and they seem to love having the room to stretch and play. Thank you in advance!
Here is a pic from about a week ago!