I haven't done VCE Sociology, I don't think many people who post often have (it is quite a small subject). But Sociology is basically the study of society. People seem to think that it is similar to psychology, but where psychologists will focus on the biology of the brain and individual behaviour (except for social psychology), sociologists will study people in groups. These groups of people (or 'society') doesn't just involve the interaction of the agency and intentions of different people, but will also have social structures and social norms and trends at play. An example is a (very) old study by Durkheim, which explained how the individual act of suicide can be related to social causes, such as social control and political systems, as well as one's level of social interaction at particular points in the year. The wiki article on it is here:
http://en.wikipedia.org/wiki/Suicide_%28book%29Social sciences such as sociology are very important because our participation in society and the fact that we live alongside others in various systems and structures which exist independently of any one person, gives us the tools we need to understand things like language, to cultivate values, to educate ourselves in specific things, etc. Without society, many theorists argue, we wouldn't have the tools necessary to do all the things we consider to be most important, like understanding the world around us, pursuing particular career goals, and living in accordance with particular values. Some would even argue that we are a 'blank slate', that our mind is completely empty, until various aspects of our society leave an imprint on us.
It is an interesting field of study, but you'll find that with the interaction of so many different factors and forces, there aren't really any easy answers in explaining human activity within a society. This, I think, is a strength of a field such as sociology.