I am a student teacher in FCTVE college in Francistown,Botswana and I am engaged in an action research project to find what could be causing lack of cooperation of learners when they are working in groups during a session.Different views are welcome from all professionals.
Often, teachers place students together and expect them to be able to work cooperatively. But, too often, children have no experience working cooperatively so they don't understand the expectations. Teachers need to teach students how to learn cooperatively in order for group work to be successful. Kagan offers a lot of techniques to help teach students expectations in group work.
It also helps to give students specific, unique tasks -- one person is responsible for recording the group's idea, one is responsible for keeping track of time, etc. When every student has a specific duty, they are less likely to argue about who gets to do what, and you're less likely to see "group hitchhikers" who do nothing.