Learning Aims:
The pupils are to learn to explain how respiration works, how oxygen is transported in the body and why the cells need oxygen in cell respiration. The pupils are also to learn to critically evaluate various statements, search for information and determine if a statement is scientifically correct. They are also to be able to justify their arguments with the support of scientific knowledge.
A picture of pupils having a discussion, textbook
Suggestions for use:

The pupils are to work in groups. Many pupils have difficulties in seeing the human body as a whole where molecules, cells, organs and organ systems work together. In this task, the pupils discuss how the various parts work together. Give the pupils the worksheet with the transcribed conversation between classmates and ask them to explain why we breathe.