Definition: With regard to relationships and human behavior, social inclusion means accepting someone into interpersonal interactions and social networks. The opposite of social inclusion is social exclusion or ostracism.
Sometimes, however, a tween may be ostracized by peers who are socially aggressive. When a tween has been ostracized, he or she may actively work toward social inclusion in order to offset the effects of social exclusion. People encourage social inclusion by becoming more compliant, conforming more often and being more cooperative with their peers. People working at social inclusion also remember social information better than people who have not been excluded. For example, an excluded tween might be able to remember exactly what each of her peers said during lunch, or be able to recall precisely what each person wore in the preceding days. In other words, when seeking social inclusion, an excluded individual takes a heightened interest in their peers' behavior.
Girls may be particularly at risk of being socially excluded, so they may be forced to develop better social reinclusion skills than boys do.
Williams, Kipling D., and Nida, Steve A. Ostracism: Consequences and Coping. Current Directions in Psychological Science. 2011. 20(2): 71-75.