This is how I see it:
Little girl gets in trouble at school for drawing how she feels because it's not bright and pretty enough. So she goes out and finds beauty in the world and draws it instead of her usual darkness. Now the teacher will feel like she "fixed" the girl despite the fact that it's only a paper thin wall over her darkness that is hiding the true problems from the world.
At first it reminded me of beyond two souls cause of the picture
I like this ending better
Little girl gets in trouble at school for drawing how she feels because it's not bright and pretty enough. So she goes out and finds beauty in the world and draws it instead of her usual darkness. Now the teacher will feel like she "fixed" the girl despite the fact that it's only a paper thin wall over her darkness that is hiding the true problems from the world.