Gritsar is right. It's funny to see them all having their playground fights but it's all very important. We have 70+ Japanese Bantams and all hell breaks loose if someone dares to roost in a higher ranking roosting spot.
Just keep an eye out (seriously - no pun intended) for them becoming overly aggressive, we've got quite few 'one eye' chickens who have come off worse from these playful antics. As they sort out their pecking order they form groups, those groups then sort out pecking orders between groups and within the groups. Normally the groups as based on clutches but we have so many going off at the same time chicks mix and match with their mums, sometimes one chick doesn't seem to get into a group, then it ends up with all the chicks dominating it and it often comes off the worse for wear.
Later, you'll find the definite cockerels do the 'staring, head on, into each others eyes until one makes the first move - that's a hoot to watch'
What color are they, do you know?