Scout has reached the point at which he no longer cares for his curly hair, and he doesn't want to cut it short.
So he borrowed a straightener from his girlfriend.
It doesn't matter to him that his older brother calls it a "Beiber-do".
It doesn't matter that his sister and I tell him how cute he is with curly hair.
None of that matters because he is learning all about what HIS likes and dislikes are, and is taking control over those aspects of his life that he can. Which I count as normal and natural for a 17 year old. After all, his brother and sister before him did the same sorts of things.
And he's getting older, so it seems natural for him to march to a different beat - be himself, go his own way, live life on (a few of) his own terms.
He's still the same Scout he always was - gentle, kind, sweet, and creative. Hopefully, he won't cringe when he sees these pics someday!