Just looked at all the pics. The ones with red are RIR and look to be pullets for now. Update us for a more accurate gender ID in a few weeks.
Also, welcome to BYC!
Much too young to sex. I see nothing that screams cockerel. The patchy-ness (red) in this case is caused from a chick getting their big boy/girl feathers which are red. The odd ball is a RIR. The others could be Brown Leghorns or Welsummers. Time will tell.
Post updated pics in a few weeks for...