desertgirl, that looks like a rooster and pullet, however, in about 10-15% of the cases, a pullet will have a larger spot and a cockerel will have some dark on the legs. I have one hen who had a huge headspot, blurry even, not much dark on the legs, much lighter coloring, but nevertheless, is now a 3 yr old hen and the mother of many chicks. When the wings feather, post pics then, because at that point, most cockerels have very wide white bars while the girls may have a bar at the end of the wing and not much else for awhile.
In your last pic, the one on the left has a bit of "frosting" that goes out from the actual distinct spot. That usually indicates cockerel, but I said usually. There are always exceptions. Neither of yours has the really dark leg fronts that my pullets always seem to have, but that can vary, too. Does one chick look sort of "faded" black and the other look deep velvety black? The faded one is usually the cockerel.