Britney 2.0 - S4-E2
Continuity mistake: In Britney 2.0, when Brittany and Santana are video calling, look at Britt's laptop. Don't look at Santana, look at Brittany. In the first shot, there's some kind of light probably a window, at the back of Brittany. In the second shot, there's no light or window at all. (00:04:10)
Continuity mistake: While Jake is singing to Marley in history class, the clock drastically changes times from one shot to the next.
Continuity mistake: When Sam is talking to and kissing Nurse Penny in her office, Nurse Penny's lanyard keeps moving from the left side (on screen) of her name badge to the right side and also sits on top of the badge. (00:43:00 - 00:45:00)
What the World Needs Now - S6-E6
Continuity mistake: When Rachel is singing the final long note of "Promises, Promises," she slowly raises her arms to above shoulder level. Then, a shot from behind shows her arms well below shoulder level, then a return to a front shot shows her arms slightly above shoulder level again.
Answer: The show is purposefully stylized and over the top. It is not designed to be an accurate, realistic representation of American high school. The idea that the glee club is so unpopular other students can literally throw garbage at them with impunity is an over-exaggeration of how glee club is considered "un-cool" compared to things like football. However, there is a second way of looking at it. The audience is simply never shown anyone getting into any trouble for throwing slushies. Just because we don't see it doesn't mean it never happened.
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