Groups in Elementary School

All of a sudden, I found myself thinking sociologically when I was doing community service with children in an elementary school.  There was three long tables where the children sit in and they all choose where to sit so most of them sit with their friends or people they like being around.  I noticed that there was one girl sitting alone at the end of the table just doing her homework and eating her snack, but she did not look happy at all she looked kind of sad,down, and in a hurry to finish.  I thought maybe she just wanted to finish all her homework without distractions until one of the other kids asked me why she was sitting alone, I didn't know exactly why, so I sat in front of her and asked why she was sitting alone.  She told me that the girls sitting behind her used to sit with her but then they were being really mean to her and excluded her out of their group.  Knowing the types of groups that there is I realized that she became part of the out-group.  She went from being a member of the in-group to a member of the out-group that was viewed with hostility by the in-group members.  After they finished their snack and some homework I turned around and she was playing with the girls that were mean to her and so when I had the chance I asked her what she did so they will talk to her again and she responded that they told her if she "helped" them with their homework they will sit with her again she thought this was a pretty good deal because she would not have to sit alone anymore.  This was an example of out-group and social exchange.  The girl became part of the out-group and for her to become part of the in-group again she had to "help" the members of the in-group with their homework.