Re: interesting puzzle but...

Why only the faces? I understand you want to hide any clothing that is gender specific but technically you're only measuring what can be distinguished from facial features. Also, some of the pictures the kids are wearing things that hide some of their features, such as the girl (I'm guessing this one is a girl) with the huge sunglasses on. Also it appears some of them might being wearing wigs which again counts as a disguise and takes away from the fairness of the test.

Our face is the most important part of us in terms of communication and therefore the great majority of the cues we take from others revolve around the face. (Yes, I'm speaking from knowledge--communications was my college major.) Yes, there are things that hide the features which would ordinarily help distinguish gender. I can promise you that no one is wearing a wig (that I know of.) This is all the children's own hair. In the case of the child with glasses on, I really don't think those glasses are hiding anything gender-specific. Remember: this is not a study; it's a game. It's not intended to be perfectly fair. I just wanted to get a quick impression of how many people can get a pretty accurate assessment of kids' gender overall. Just have fun with it.