The scientific method is a method for conducting an objective investigation. The scientific method involves making observations and conducting an experiment to test a hypothesis. The number of steps of the scientific method isn't standard. Some texts and instructors break up the scientific method into more or fewer steps. Some people start listing steps with the hypothesis, but since a hypothesis is based on observations (even if they aren't formal), the hypothesis usually is considered to be the second step. Here are the usual steps of the scientific method.
Scientific Method Step 1: Make Observations - Ask a Question
You may think the hypothesis is the start of the scientific method, but you will have made some observations first, even if they were informal. What you observe leads you to ask a question or identify a problem.
Scientific Method Step 2: Propose a Hypothesis
It's easiest to test the null or no-difference hypothesis because you can prove it to be wrong. It's practically impossible to prove a hypothesis is correct.
Scientific Method Step 3: Design an Experiment to Test the Hypothesis
When you design an experiment, you are controlling and measuring variables. There are three types of variables:
You can have as many controlled variables as you like. These are parts of the experiment that you try to keep constant throughout an experiment so that they won't interfere with your test. Writing down controlled variables is a good idea because it helps make your experiment reproducible, which is important in science! If you have trouble duplicating results from one experiment to another, there may be a controlled variable that you missed.
This is the variable you control.
This is the variable you measure. It is called the dependent variable because it depends on the independent variable.
Scientific Method Step 4: Take and Analyze Data
Record experimental data, present the data in the form of a chart or graph, if applicable. You may wish to perform a statistical analysis of the data.
Scientific Method Step 5: Accept or Reject the Hypothesis
Do you accept or reject the hypothesis? Communicate your conclusion and explain it.
Scientific Method Step 6: Revise the Hypothesis (Rejected) or Draw Conclusions (Accepted)
These steps also are common:
Scientific Method Step 1: Ask a Question
You can ask any question, providing you can devise a way to answer the question! Yes/no questions are common because they are relatively easy to test. You can ask a question where you want to know whether a variable has no effect, greater effect, or lesser effect if you can measure changes in your variable. Try to avoid questions that are qualitative in nature. For example, it's harder to measure whether people like one color more than another, yet you can measure how many cars of a particular color are purchased or what color crayon gets used the most.
Scientific Method Step 2: Make Observations and Conduct Background Research
Scientific Method Step 3: Propose a Hypothesis
Scientific Method Step 4: Design an Experiment to Test the Hypothesis
Scientific Method Step 5: Test the Hypothesis
Scientific Method Step 6: Accept or Reject the Hypothesis
Revise a Rejected Hypothesis (return to step 3) or Draw Conclusions (Accepted)
Learn MoreScientific Method Lesson Plan
Scientific Method Quiz #1
Scientific Method Quiz #2
What Is an Experiment?