I saw this video in college, and I immediately changed my major.
In the clip, a teacher in Iowa, Jane Elliott, conducts a study on her students that will be talked about for decades. She re-creates segregation and racism in her classroom using a "brown eyes/blue eyes" experiment. She flips the entire class on their heads by switching the roles and makes a most profound discovery about us all. In the end, the students learn something the world today is still struggling to.
There are too many great moments to point out. The payoff at the end is brilliant and a perfect metaphor for what we deal with and face every day in our society. Like "Catcher in the Rye" is to high school students, this is part of your Upworthy required reading.
Note: The 1970 ABC News video clip accompanying this post was removed from YouTube and other outlets. But the full documentary about the experiment including original news footage, "A Class Divided," is available for free on the PBS "Frontline" website (Flash player version).