It is summer of 1954 and the kids in a small camp in Robber's Cave State Park (in Oklahoma) are divided into the "Eagles" versus the "Rattlers." We had a version of this called "color wars" when I went to camp back in the 1970s.
The counselors and other camp staff used every trick in the book to, in a friendly way, get the teams to build strong bonds within their groups and to truly despise (again, in a kind of benign way ...) everything and everyone connected with the other group.
Competition between the groups was fostered and strong ingroup favoritism and outgroup hostility (see Billig & Tajfel, 1973) were quickly and easily elicited.
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