Learning Objective

In this lesson we will learn how scientific knowledge is accumulated through a rigorous and methodical process of inquiry.

Learning Outcomes

By the end of this lesson you will be able to:

  • Describe the steps involved in the scientific method.
  • Define qualitative and quantitative observation, inference and prediction.
  • Describe how a fair test is conducted, including independent and dependent variables, control variables, test groups and control groups.
  • Explain how the accumulation of scientific knowledge may lead to theories or laws, and differentiate between the two.

the scientific method lesson contents

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Lesson Topics

1 | Overview of the Scientific Method

2 | Making Observations

3 | Inferring and Predicting

4 | Conducting a Fair Test

5 | Interpreting Results and Making Conclusions

6 | Development of Theories and Laws


Lesson Summary

  • The scientific method is a systematic approach that characterises the way in which scientific knowledge is acquired.
  • The main steps in the scientific method are:
  • Making an observation.
  • Making an inference and prediction.
  • Conducting an experiment.
  • Developing a theory or law.
  • An observation involves noticing and recording a particular occurrence.
  • Qualitative observations relate to qualities and involve descriptions. They are subjective and usually involve our senses.
  • Quantitative observations relate to quantities and involve measurements. They are objective and involve numerical values and units of measurement.
  • An inference is an interpretation of an observation and an attempt to explain it.
  • A hypothesis is a prediction based on an inference.
  • A fair test or controlled experiment is an investigation that tests a hypothesis.
  • A variable is any factor that can change during an experiment.
  • A dependent variable is a factor being measured during an experiment.
  • An independent variable is the factor being investigated during an experiment, by observing what effect it has on the dependent variable.
  • A control variable is any factor kept constant during an experiment.
  • A test group (experimental group) has a modified form of the independent variable in an experiment.
  • A control group has an unmodified form of the independent variable in an experiment.
  • Following an experiment, a hypothesis is either accepted or rejected, or may require further testing if the results are inconclusive.
  • Experimental results often create new questions that can be tested.
  • The acquisition of scientific knowledge is a continual process.
  • When a hypothesis is tested multiple times with the same result, it may lead to the development of either a theory or a law.
  • A theory is an explanation of some aspect of the natural world that has been well-substantiated by multiple tests.
  • A theory is an interpretation that can evolve as new evidence is acquired. However, it can never become a law.
  • A law is a descriptive generalisation about some aspect of the natural world that holds true all of the time.
  • A law is constant and not subject to change.
  • A scientific fact is an occurrence that has been repeatedly confirmed by testing.

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