I recently began experimenting with more advanced group work techniques after being drawn to them for a number of reasons over the last few years. My previous classes were too challenging for me as a beginning teacher to even think about attempting anything requiring so much student responsibility.
The first step that I took was attempting to divide the class up into home groups and expert groups. Depending on student numbers this can be quite challenging and until you actually do it, seeing the impact of different choices can be hard to anticipate, so there may be some need for alterations in group composition at some point in order to get a better distribution of students numbers, but it is important to also pay attention to relative student ability. Differentiated learning can work best if the students are mixed up and not separated according to ability.
Next I introduced some basic group work into the following lessons in order to get the students used to working in groups as well as in their specific groups. I would switch between having them work in their home groups and expert groups. The tasks I set them initially were very basic, covering content that they were already familiar with in order to allow them to focus on the group work concept and not be overly distracted by challenging material in a foreign language.
I gradually started developing tasks that implemented the jigsaw approach, starting them in their expert groups and then switching them to their home groups. Reporting at this phase remained verbal and the focus was still on training them in the mechanisms of jigsawing.
Two weeks ago I finally set them their first full written Jigsawing task. I made sure that each home group submitted a written report and asked that each student’s contribution be labelled with their name. The results were very pleasing for my ‘A’ class, with my ‘B’ class needing a little more practice and feedback from their previous efforts.
I believe that this lesson was one of the most effective lessons that I have led all year in terms of student engagement, levels of learning backed up with evidence of learning, ability to have a feedback loop with the students about their learning, higher order thinking, personal responsibility and several other factors I can’t think of off the top of my head.
Good group work lessons do require more forward planning and can be difficult to implement for this reason, however the effort is definitely worth the results.

Great. If I remember correctly there are some good youtube vids explaining how to get started with jigsawing as well. Maybe you could post some of you favourites up here ^_^
Not a bad idea Hugh. It means I might actually check some of them out myself.