At first, the defense of the Homeland goes well, with the children blowing up large numbers of American Naval, uh ... tanks?
Whatever they are, they're no match for giant exploding pencils.
Between the flashy missiles, the patriotic music and the impressive explosions, things are all inspirational and it looks like the day is won ... until. The main character is way too inaccurate to hit the ships closing in on him. He frantically tries to calibrate his shots, but since he can't use his giant protractor properly his aim is off and American missiles get through.
Although to be fair, America is using Bullet Bills, which can be a real pain.
One of them hits him, and the music turns grim as American vessels close in. His friends come to his aid (as shown with a Batman-esque red star wipe), but -- gasp -- it looks to be too late. Then, the dream ends and our protagonist awakes with a newfound desire to study. He's going to get those Americans next time!
There's a fine line between folksy and half-assed.
The moral of the story:
"Do your homework, or enemy forces will kill your ass."
Better math could have prevented this.