The two main children, Wren and Noah, from my yet to be published comic. Because they are children. They are also gifted children, but none of that precocious, talking-like-a-small-adult crap. Even genius kids still act like kids and are naive about the world at large.
Also, they don't default dress like this, they're just going to a Renaissance Fair. And I legit saw kids dressed up this way at the one I recently went to, it was awesome.