Teaching The Scientific Method: Hypothesis

If you teach primary science, you will inevitably find yourself teaching the scientific method.2013-updated_scientific-method-steps_v6

  1. Asking A Question
  2. Background Research/Knowledge
  3. Hypothesis
  4. Design Experiment
  5. Test and Retest
  6. Analyze Data
  7. Draw Conclusions
  8. Communicate Results

In order to teach students how to write a hypothesis, you must first give them background knowledge. This is imperative. Elementary students are, by definition studying elementary topics, even top students will have a relatively low level of background knowledge.

In short, you must plan out what your students will need to know before they begin a lab. What background knowledge do they need? How will you make sure they know it before the lab?

 After your students have made observations and obtained the necessary background knowledge, they can begin working on their hypothesis.

Hypothesis: An idea that helps you learn about the world that is testable and repeatable

I start by teaching what testable and repeatable are by using a seemingly ridiculous hypothesis. “If I let go of this pen, then it will go up because of the force of gravity.”

Students think it is funny because the hypothesis is obviously wrong. And I want them to know it is wrong! So I repeat the phrase, and let the pen go to test my hypothesis. Next, I ask my students what happened. Finally I repeat the hypothesis and experiment.

Then I ask, “Was the hypothesis testable?” and “Could I repeat the experiment?” And I follow that with, “Was my hypothesis correct?” 

This leads to something many students find counterintuitive. A hypothesis can be both valid and wrong. Over the course of a school year, I will repeatedly ask my students if a hypothesis can be wrong and be valid because it is important.

Writing A Hypothesis

Then, when we begin working on writing hypotheses. I teach my students to use the “If….Then…Because…” format. I always keep the format the same. This makes the scientific method easier to learn because this step is never changes and makes it easier for students to focus on the science content.

The Variables

Next, I teach my students about variables by writing the definitions and linking them to my hypothesis and the If, Then, Because format.

Independent variable: The variable you change
The ‘If’ statement identifies the independent variable/s (what the student changes).
Letting go of the pen is the independent variable.

Dependent variable: The variable you measure
The ‘Then’ statement identifies the dependent variable/s (what the student measures).
What happens to the pen is the dependent variable.

Next we go over the control variable.
Control variable: What you must keep the same
The height and force that the pen is let go with must be the same in every trial of the experiment.

The Reason

The ‘Because’ statement identifies the proposed reason “something” will happen. This should be based on their background knowledge that you have already taught them.
The force of gravity is the proposed reason.

Putting It All Together

The ‘If’ statement identifies the independent variable/s (what the student changes).
The ‘Then’ statement identifies the dependent variable/s (what the student measures).
The ‘Because’ statement identifies the proposed reason “something” will happen.

What I do in the next class is to have students practice identifying variables in various experiments. Generally, elementary students will be better at identifying control variables than discriminating between independent and dependent variables. That is fine. Expect them to struggle initially and give them regular practice. They will improve. You will improve in your explanations and examples too! Hypotheses are tricky. Work at them and practice it with your students.

2 thoughts on “Teaching The Scientific Method: Hypothesis

  1. Pingback: Teaching The Scientific Method: Asking A Question | TeachingScience

  2. Pingback: Teaching The Scientific Method: Background Research | TeachingScience

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