Alright, my cousin came over to visit and he's leaving tomorrow, he's only 9 and his DS is broken.
The touchscreen is completely blank, there's no picture. But you can still touch it and it works, when you look at the top screen carefully, you can see the touchscreen's contents VERY faintly in the background. I'm guessing that when he dropped the DS, the bottom screen's picture somehow got knocked up to the top screen :/ Also, when you look at the bottom screen at an angle from the bottom of the DS where the GBA slot is, you can see a lot of vertical colored lines running along the touchscreen.
Is this fixable, will I have to send it to Nintendo to get it fixed, or is the DS screwed?