Group members must realize they need each other in order to achieve success.
There are many ways that positive interdependence can be facilitated.
Any task or problem given to the group should be difficult or time-consuming enough so that it will be too much for a single student, so group problems or tasks are necessarily different from those given to individuals. (This is sometimes overlooked by instructors who give groups problems that each person can solve quite easily. This can result in members working independently rather than cooperatively.)
Problems that have no unique solutions or require divergent thinking are also preferable.
In the business world, groups are formed to take advantage of different background knowledge and skills. This may not be possible in the classroom except for certain kinds of tasks that require (say) writing, mathematics, graphics, and computer skills and you have a good mix of such skills among the students.
This means that the groups must have common goals so that there is a benefit to having each student in the group learn and make sure all others in the group also learn. In other words, students must be placed in a situation where they all sink or swim together and there is no advantage in one person abandoning the others.
An individual bonus can be awarded to each member of the group if all members of group succeed in achieving a predetermined level of performance. Another method is to give a single grade to all members of the group for the group effort (i.e., group grades).
Restricted or shared resources
Students can be made to collaborate if they are restricted in the resources made available to them. This happens naturally in the case of expensive laboratory equipment. But it can also be done deliberately by giving just a single handout to the group or by giving different information to different members of the group.
By making different people responsible for different tasks or aspects of the problem, you can prevent one student from trying to do everything. Students learn how to take on responsibility and how to depend on others.
These are problems in which the main idea of the problem is embedded in a complex story line that features the reader in a problem-solving role. They are preferable to the more traditional bare-bones problems which have been stripped of all but the most essential elements needed to solve the problem because students learn what to do by discussing what the problem is all about.
This involves having group members edit or correct the work of other group members before it is handed in.
Each member of the group is assigned a different task but is required to teach every other member what he or she has learned. Eventually, every member of the group is responsible for knowing all the material.