My daughter is in grade 3, same thing. I figured out what it was; her friends from second grade had a ring leader, my daughter is cute, good in sports, smart ect. ect. so the ringleader had the other 2 girls ignore my daughter the following year. I have seen her attempt this with my daughter against another child in Grade 2, my daughter just said, 'no, I like her, I don't know what you mean.' Grade 3 rolls around, her friend she stood up for moves, and those 3 girls ostricize her. My daughter is now friends with only boys. I learned that she had asked her best friend from last year over 5x, recieved rejections everytime. I learned that the ringleader said she would only come over when we had our backyard pool clean and running, but no until then. It is that disgusting. I spoke to parents - two of them could care a less and said 'let the girls work it out' another one was shocked that their daughter was like that and insisted she come over. She did and acted very carefully around me as she knew she wasn't very nice to my kid. In anycase, I did report this cliqueyness to my daughter's teacher, she got on it, the principal got on it and insisted our daughter join the school track team, make a speech at the district, you name it...my kid's in a great school. On my end, I had the nieghbourhood girls come over, had her in camps all summer and have her on a sportsteam for the fall. My daughter has great self esteem, yet doesn't recognize her one friend's manipulations. She's just had it, 'girls are stupid, so I want to be friends with boys...' So be it...