In 1954, 22 lower middle class 11-year-old Protestant boys from Oklahoma City, Oklahoma of similar lower middleclass backgrounds, unacquainted with each other and carefully screened for psychological stability and adjustment, boarded two buses bound for a 200-acre Boy Scouts of America summer camp near Robbers Cave State Park in Oklahoma.
Observing all of this from his perspective as camp ‘janitor’ was the architect of the study, Muzafer Sherif, a Turkish-born Harvard graduate, later credited with founding the discipline of social psychology.  What the boys did not know, in these days before informed consent, was that they were to about to become guinea pigs in one of the most fascinating and beloved psychological studies of group behavior in history.
For the first several days, the camp counselors (all a team of psychologists, including Sherif’s wife) encouraged each group to engage in activities to solidify their bond with members of their own group.  Each group chose a name — the Rattlers and the Eagles; each created their group’s own ‘flags’, designated places in the camp as theirs; wrote songs; chose practices and even particular modes of behavior as exclusively ‘theirs’.
Within a few days, both the Rattlers and the Eagles had firmly congealed as a group, with their own social hierarchies and leaders; each, as psychologists would put it, had firmly created an  ‘in-group’.   The Rattlers and Eagles were assigned separate living quarters far apart from each other. At no point during this initial bonding period were they allowed to meet any members of the other group.
Engineered conflict
It was now time to test the effect of such intense ‘in group’ bonding on outsiders.  In the next phase of the study, Sherif and researchers engineered situations designed to be highly competitive and frustrating in order to deliberately bring the two groups in conflict. 
They announced a general tournament — with baseball, other competitive games like tug of war, tent pitching, cabin inspection, and skits and songs culminating with a treasure hunt over four days.  A trophy, medals and 11 four-bladed Swiss Army-style knives were held up as the much coveted prizes to the winning team.
Before the competition had even started, the boys had laid claim to certain sections of the playing fields; the Rattlers placed their flag on the field backstop and the Eagles attached their flag to a pole, announcing it would never touch the ground.  Finally, after a day spent practicing, both groups finally laid eyes on the already loathed other.
Over the four days of the competition, the staff manipulated the scorekeeping so that the scores remained neck and neck, and also ensured the two teams were constantly made aware of the closeness of the race.  Good sportsmanship gave way to name-calling, invectives and such discrimination between groups that the Rattlers and Eagles refused to have virtually anything to do with each other outside of the tournament.   
Out of control
After a while, the experimenters didn’t have to engineer anything. Decking themselves out commando-style, the Rattlers raided the Eagles cabin, turning over beds and ripping mosquito netting.  Armed with sticks and bats, the Eagles retaliated with interest, throwing allthe Rattlers’ belongings in a heap in the center of the cabin.  The Rattlers posted their own flags on everything that was ‘theirs’ — their cabin, the swimming hole, the upper camp, even the baseball diamond. The Rattlers tore up the Eagles’ flags; the Eagles burned the Rattler’s flags.
On the day the Eagles won the tournament, the Rattlers raided and stole the prize knives. By this time every boy refused even to eat when any member of the opposing group was present in the same food hall. Sherif and his team once found the two groups lined up across from each other, as if ‘separated by an invisible line’, which shortly degenerated into a fist fight that had to be broken up.
Having escalated such fierce prejudice between the groups, the Sherifs then experimented with methods of positive discrimination.  The counselors set up a series of activities that would encourage the two groups to co-mingle and get to know each other: bean collecting, watching a movie, shooting firecrackers on the Fourth of July. 
Nevertheless, all attempts at social engineering failed; no amount of basic contact between the boys seemed to lessen the tension, and on several occasions members of the Rattlers and Eagles even got into a food fight.
Camp crises
The Sherifs then hit upon the idea of creating a series of crises in the camp that could not be solved without the resources and participation of all of the individuals within both groups. After the drinking water suddenly dried up and the boys discovered a large sack stuffed into an outlet faucet of the water reservoir — the work of vandals, a camp counselor told them — both groups had to work together to figure out how to clear it. 
The Rattlers and Eagles were also enlisted to pull a rope together in order to clear a partly cut through tree that may have posed a danger and were then asked to help move a truck carrying food for both groups that had got stuck in a rut.
As the boys got involved in these kinds of large goals, the ice between them began to thaw.  During the water incident, once the water began flowing again, the Rattlers allowed the Eagles to drink first from the fountain, because they hadn’t brought their canteens and were thirstier.  After working together to finance a movie, they began eating together in the mess hall, with Rattlers freely mixing with Eagles.
 On the final day of camp, the boys unanimously voted to travel together on the same bus.  At a stop on the way, the leader of the Rattlers spent all of the $5 he’d won on a bean toss contest on malted milks for all 22 boys.
Walls and bridges
Discrimination doesn’t require conflict or indeed much besides the flimsiest designation of otherness.  As American psychologist Henri Taifel demonstrated in a study, when a batch of adolescent boys were simply told that certain others had scored the same score as them at a computer task, they began to band together and discriminate against those who hadn’t achieved the same score.
Difference of any sort that gets emphasized is enough to create a ‘minimal group’ and, consequently, an outgroup. All it takes is any kind of a wall, no matter how flimsy.
William Golding described what he saw as the inherent ‘darkness of man’s heart’ in Lord of the Flies: when the veneer of civilization is removed, even children are capable of turning savage.
Sherif’s study demonstrates the opposite. School boys indeed are fully capable of turning cruel and bully boy toward each if they are placed in opposing groups and forced to compete over scarce resources. 
But when the Robbers Cave children were given a common goal and purpose – larger than themselves and their group – they readily put aside their differences to work together cooperatively. 
Maybe we adults can take some lessons from these 11 year olds about the power of a ‘supergroup’ and also the power of reaching across the aisle.