I doubt that there's any way actually to stop it, from a site administrator's perspective. The best way to end it soon is simply to ignore those questions. The children posting them will eventually get bored and find some other way to spend their apparently excessive free time. ;o)

Lol. How do you make cookies ? ;) I hope they make it stop soon. It's making me sad.

Apparently someone in the UK broadcasted, published or tweeted about this. Seems like they may have missed the core of it though.