While this unit can be adapted to suit particular classgroups, we suggested that it is presented as a problem solving exercise by the teacher. In this unit normally the teacher introduces the problem through advertisements referring to chitosan as a slimming agent: "Chitosan: Fat Magnet!" These advertisements can be sourced by the teacher or perhaps the students. It is expected that if the information was found on the internet, then they would be confronted with other information claiming the uselessness of chitosan for reducing weight. So a problem arises, as there are two contradicting contributions, one in favour of chitosan as slimming agent, and another describing that it does not work. Thus the leading question for this unit: "Who is right?" which is the starting point for the class' inquiry process. During the course of this unit the students need to:
- define the problem,
- develop and carry out a plan of how to investigate the problem (which includes
- search for further information,
- formulate and test hypotheses,
- plan and carry out experiments,
- communicate and discuss their findings with peers)
- and create coherent arguments supporting their findings.
In addition they will be asked to make and discuss own decisions whether to use chitosan themselves or recommend it to others.