Did Principal Skinner make a mistake when he offered his prized student a ride on a submarine. "Yellow Subterfuge" is the seventh episode of the show's 25th season.
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A picture of Principal W. Seymour Skinner in all his glory saluting. Poor skinner is a vietnam vet and tries so hard to be a good man, but succumbs to the will of his mother and Bart Simpson.
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The Simpsons Quotes

Homer: (Wearing glasses) The sum of the square roots of any two sides of an isosceles triangle is equal to the square root of the remaining side!
Man: (From inside a bathroom stall.) That's a right triangle, you idiot!
Homer: D'oh!

Mr. Burns: Oh, and one more thing: you must find the jade monkey before the next full moon.
Smithers Actually sir, we found the jade monkey. It was in your glove compartment.
Mr. Burns: And the road maps, and ice scraper?
Smithers: They were in there too, sir.
Mr. Burns: Excellent! It's all falling into place...