A good topic to teach to actively foster cooperative learning is "How The Ear Works." After a lesson about the ear and it's anatomy, students would be tested, at the end of the unit, on how the ear actually functions via a group "experiment." Students would be asked to construct a large model of the ear with given materials. After completing their model, the students would present their findings to the class by explaining each piece of the model and it's function.
The groups for my lesson would include 3-4 diverse members. Boys and girls alike would be a part of the group all with complementing skills. Students would get along or challenge each other may be in groups together, but members who push each other off task would be separate. For the ear model, I may choose at least one boy and girl who typically work well together. From here I may choose other complementing members of the class, though this would not be the only technique I used. Constructing an ear model would be a good way to get a diverse group of individuals working together.
To foster interdependence of group members I would assign each member a specific task. There would be one member who is the script, or writer. Another member who is responsible for finding materials and communication instruction. And two members to actually assemble the model. Though member have specific tasks, all would be encouraged to give their input about the construction and explanation of the model.
To assess what students have learned I would actively visit each group as they work to track their progress. By attending to their work and conversations, I would be able to foster help if a group needs it. I may also redirect the group's current ideas if they are off topic. Additionally, by having students present their model's, I would also foster accountability which may motivate students.
To enhance students’ ability to work cooperatively with their peers over the long run I would would provide each group (as a whole!) reward for hard or successful work as well as allow members to secretly evaluate each their work. If groups are rewarded, they are likely to want to work together again in hopes of more reward. Through evaluating the groups success, each member would be able to express what they liked and didn't like about it allowing me, as their teacher, more access to their feelings and needs. I would make sure evaluations were focused on criticizing ideas and behavior rather than people themselves. Based on the evaluations and performance I would then be able to decide the best techniques for future groups to learn as much as they can.