I don't like working in a group that much (maybe because I'm a maverick), but if I have to work in a group in school, I don't complain and try to do my best to contribute to the group work, because nothing else matters.
I'm currently working on a three months project with 5 other group members at school. There are some advantages and disadvantages. Bad thing is that many of my group members may be good at school, but they are a bit lazy so they wag school lessons more often than other people in my class. This is what makes them a bit unreliable. An advantage of the team work is that it is often entertaining and one person doesn't have to do all the work (because the work is separated for each person, logically).
My advice: Just be friendly, open-minded and "funny". It will improve the working atmosphere if you laugh sometimes with your group members.