Andrew, Geoffrey, Kathrine, Cassie, and Justine Often Do Things as a Group

Andrew, Geoffrey, Kathrine, Cassie, and Justine often do things as a group on weekends. Considering general developmental trends in youngsters' social development and without knowing anything else about these five young people, we would guess that they are probably:

A) In kindergarten or first grade
B) In third or fourth grade
C) In fifth or sixth grade
D) In high school