Little Girl I Wanna Marry You - S1-E13
Other mistake: Coach Taylor and Tami moved to town before the season. Tami is asked to work on the mayor's reelection campaign. Coach Taylor asks Tami "Does she know you voted for her opponent?" This wouldn't be possible as the previous election would have occurred years before the Taylors moved to town.
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Suggested correction: Didn't they say he was the middle school coach before being named head coach? That's why he was Jason's coach ahead of being his high school coach.