Bubble diagrams come in two flavours - single and double.
Single bubble diagrams are best used as a kind of brainstorming tool. The title or central idea is written in a circle in the centre of the page and all other ideas are written in circles that always stem from this centre.
Once drawn, the ideas can be used as a basis for discussion or can be grouped in categories and turned into a mind map.
Double bubble diagrams are used for comparing two things, such as: Two characters from a story, two differing viewpoints or two approaches to a problem.
In the diagram above, the bubbles joined to both concepts are areas both have in common. The bubbles to the left are areas that apply only to concept 1, and those to the right those areas that apply only to concept 2.
A good way to draw a double bubble diagram is to start with two separate single bubble diagrams, one for each view point or character. Two different students could do one each. The diagrams can then be placed side by side - this is an excellent way to start discussion - and areas of difference or commonality identified.
Click here for a rough example of using bubble diagrams for conflict resolution.
Click here for an example of using a bubble diagram to evaluate a college visit.