You may be given a stimulus (like a piece of text or an object) as the focus of a group discussion.
If you are given a stimulus in advance, this will give you time to research your topic and to decide how you intend to respond to the stimulus you have been given.
The stimulus may introduce a topic of controversy and therefore encourage different points of view. For example, you may be given information regarding migration and each member of your group will need to respond to the material. Some of your class mates will agree with the material whilst others will not. This does not matter; in fact it is better if there are a variety of different viewpoints in the group as this will lead to a more interesting discussion.
The most effective way of responding to the stimulus is by providing a thoughtful, detailed argument. Remember to include plenty of reasons for your opinion. It is important that you include evidence to support what you say. This evidence may come in the form of anecdotes, statistics, the opinions of other people you have talked to during your research, or quotes from books or internet sites.
You must present your points in a logical and clear manner. Do not worry if someone has a different point of view from you - continue to make your points in a confident way. Your comments are expected to be mature and perceptive; you should suggest reasons to explain why you have a particular point of view and you should be able to summarise your points throughout the discussion.