Explain to students how the factory model delivers oxygen.
Organize students into groups, provide each group with an assortment
of craft materials, and ask each group to re-create the model.
When the models are finished, have students brainstorm things that
could go wrong in the process and interfere with the delivery system.
(See things
that could go wrong in the factory model for suggestions.)
Ask each group to alter its model in a way that interferes with the
delivery process.
Discuss the results.
Display a diagram of the human circulatory system and encourage students
to make analogies between the factory model and the parts of the human
circulatory system.
Ask them to relate the things that went wrong in the factory models
with things that can go wrong in the human circulatory system.
Discuss with students the things they can do to avoid those problems
and keep their hearts and circulatory systems healthy.