First one looks like it might be starting to get streamers and the comb is a little bigger so I'd say possibly cockerel on that one. The second one is still hard to tell, but the comb looks pretty small still so could be a pullet. The third one I'm leaning towards a pullet. Smaller comb and the crest is pretty much sticking up and not jetting back.
So hard to tell with these silkies!!! I went back in forth with my white silkie hen until she finally laid an egg! Although I pretty much was thinking female by about 8 weeks just by her demeanor. If there are ones that challenge one another and chest bump or stand up real tall to another one then those ones tend to be males. The more docile sometimes skittish ones when they're young tend to be females. This is not always true of course, but it's what I've generally seen in my chicks.