Science is limited to natural explanations. The natural world refers to that which is perceived directly or indirectly by our senses. Given a list of topics, students will be able to determine which are suitable subjects for scientific exploration, and which are not. Given a list of descriptive traits, students will be able to say which are characteristic of modern science, and which are not. If possible, give your students a short Science Knowledge Survey on the nature of science, to assess their understanding of this topic.
Teacher realizes that there are other questions possible, but keys in on the last question.
A mechanic can only correct a mechanical flaw. She has no way of seeing a demon, let alone fixing or getting rid of one. To the owner, the demon may be causing the intake flow problem, but that is of no concern to the mechanic. She does not know if demons exist because they are not measurable . This is a natural cause which explains the naturally occurring event.