Too young to guess breed or gender. There are simply too many different breeds that those could be. Try again between 6 to 8 weeks old, when they are feathered in.
With my experience, I feel that the first and fivth chicks are male. I am not sure about the other chicks, but that's what I think about them two because their wing feathers are so much shorter then everyone else's. Males usually feather in much slower. Take what I say with a grain of salt though, cause you never 100% know until the lay an egg or crow