Why is Mädchen neutral?
Why is Mädchen neutral? Why does Das go in front of it, when Mädchen is clearly female?
Jarryaany is right. Das Mädchen is a diminutive of die Magd (the maid). Any German noun that ends with -chen will have the neuter definite article, das. In German, grammatical gender doesn't always match biological gender. One example of this is when referring back to something with "it".
Ich habe eine Katze. Sie is schwarz. - I have a cat. It is black. - "Cat" is grammatically feminine (die Katze) so in the second sentence, "sie" means "it" and not "she". It has nothing to do with the cat being a female cat; it has to do with the word being grammatically feminine.
What the others said. BTW, you're not the first to wonder about that. When Mark Twain tried to learn German in the 19th century, he wrote: "In German, a young lady has no sex, while a turnip has. Think what overwrought reverence that shows for the turnip, and what callous disrespect for the girl." :)
It's interesting to know the origin of the word Mädchen from Magd, it makes it all a bit more understandable. It's a very complex and convoluted process by which language originates.
I just found out that a male cat is der Kater - so I guess that means die Katze is probably, technically, a female cat.