South Park - 4th Grade Season 4 Episode 11
When the boys finally get to fourth grade, they begin to feel nostalgic for third grade. They get a couple of college students to morph Timmy's wheelchair into a time machine so they can go back. Meanwhile the new fourth grade teacher, Ms.Choksondik, seeks Mr. Garrison's advice for dealing with the boys, and Mr. Garrison attempts to come to terms with his own sexuality.
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