How do peer groups impact Elementary school life?

As children reach the stage of elementary school in their life, a certain change begins to set in. Peer groups, or being around other students, become increasingly influential on the lives of these children, sometimes even overpowering the influence that parents can have on a child. When a child reaches first grade, it is seen that they turn to adults for a safety valve where they can ask questions and receive affection or comfort when needed. At this level the student is still dependent on the adults in their life to help them through difficult and uncomfortable situations. At about second grade, the students begin to seperate themselves between male and female. The boys tend to be more adventurous as a whole then the female students. The gender barrier becomes a great problem due to the fact the students seem to think that it is almost wrong or embarrassing to befriend the opposite sex. This can be seen in almost any persons experience through elementary school, when students start making rumors or if one student "likes" another it is blown up through the young emotions and immaturity.
I feel it is important for the teacher to try and break this barrier in any way that they can, such as assigning groups of both genders working together or opposite gender partners. I believe its tough for students to get along ad act normal during this stage of their lives because of the fact they are experiencing changes and new challnges but the teacher has to understand this and make the best environment for everyone to feel welcome and comfortable. It has to be seen when students are being left out or being made fun of by the other students. The teacher has to maintain control of being able to mix all the students together and help them grow as learners and people, even at this young age.