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!

Lisa: Mr. Blackheart, are you an ivory dealer?
Mr. Blackheart: Well, I've had lots of jobs in my day: whale hunter, seal clubber, president of the fox network. And, like most people, yeah I've dealt a little ivory.