Earth Science Class Day Three

During the third day of Earth Science class, we discussed the scientific method.  I share personal stories of when I fix computers and how I use the scientific method to do so.  I start off by talking about clients bringing me a computer that turns on but won't display anything.  

• Initial observation of phenomenon: Computer turns on, but no display.
• Question:  Why doesn't the computer display anything even when the power is running?
• Hypothesis:  Could be that ram, motherboard, or some connection issue.
  • I discuss with students that the hypothesis is not just a guess, but an educated guess based on previous experience and knowledge.  My gut tells me that it is the motherboard.
  • I discuss with students that you want to test each of these separately, starting with the most obvious and cheapest possibility.
• Experimentation:  Experimentation occurs when scientists perform tests to prove or disprove the hypothesis.  At this point I talk about a hypothesis needing to be testable and falsifiable.
  • The most obvious would be the motherboard, but that is not the cheapest, so I might as well test the ram, then the connection.  If neither one of those work, then it is most likely the motherboard.  I can now replace the motherboard.
  • These changes during the experimentation phase are variables.  I discuss that variables are changed one at a time.  I don't change the motherboard, play with the ram and check cables all at once.  I do one at a time.
    • I also discuss that there are two different variables that go hand in hand: the independent and the dependent.
      • We discussed each of these, gave them examples and then had each table group create their own independent and dependent variable pair example.
      • I also compared independent and dependent variables to math tables that have an "x" and a "y" column.
• ​​Control:  We discussed the purpose of having a control during some experiments.  I did this by discussing how doctors test for allergies when using the skin prick test; comparing different allergen skin reactions to a normal saline solution allergen.  The saline solution was of course the control.
• Conclusion: I discuss that the conclusion is usually a statement about what the experiment test result was.  In the computer case, it was that the motherboard needed to be replaced.  In the allergy testing, it was that the baby was allergic to certain allergens.
• Now to put this in practice students need an opportunity to prove that they understand the scientific method.
  • We first watched the video about Brooke and her ability to climb rocks.  One purpose of the video was to first of all show that success is determined by how much effort is put into practice, and that successful people have drive.  The second reason is so that they can observe rock climbing so that their mind is set on this subject.
  • I have the students get with their table groups to discover which person has the best rock climbing shoes on their feet at this very moment.
    • Students have to come up with a question, hypothesis, experiment (step by step description on what they did), data, variables that they tried and a conclusive statement.
    • An advantage of this lesson is that it is at the beginning of the year, so students have to get to know each other a little better to discover the answer to their question.
    • Most students will not get this right.  They don't experiment, they are afraid to take off their shoes, they each try their own shoes and have no idea of how to compare forces that are equal so that they can eliminate variables.
      • It is OK though that they get this wrong.  When they present their experiment, I poke holes in it to get the thinking.  As the year progresses they will get better.  Just don't accept their answers all the way, unless of course it is perfect.  I can usually find a flaw in every first experiment.