Scientific Methods

Scientific Methods

• What are a few things you notice about this video of dry ice in water?
• What do you wonder?
• Write one question you have based on your observations.

Step 1: Make an Observation

• Observations are how scientific investigations begin.
• Scientists can make observations by using their senses. Senses include:
• Sight
• Hearing
• Smell
• Touch
• Taste

• You make observations all the time!
• Think about how often you say, "That looks interesting," or, "What was that noise?"

My example observation is: "I've noticed my dogs bark when they hear an unfamiliar sound, but they do not bark at unfamiliar people!"

Step 2: Ask a Question

• After scientists make an observation, they ask questions about what they've observed.

• For my example, the question I would ask about my observation could be:
• "Do dogs bark more when they see a stranger or when they hear an unfamiliar sound?"

My example question is: "Do dogs bark more when they see a stranger, or when they hear an unfamiliar sound?"

Step 3: Form a Hypothesis

• Your question will lead you to form a hypothesis!

• A hypothesis is an educated guess, or prediction that can be tested.
• It's a possible explanation for something that you can test through observation and experiments or studies.

An example of a hypothesis for my dog example could be: "If a dog sees a stranger, it will bark more than when it hears an unfamiliar sound."

My example hypothesis is: "If a dog sees a stranger, it will bark more than when it hears an unfamiliar sound."

Step 4: Set up an Experiment

• When you are ready to set up your experiment, here are some steps to take:

1. Consider your factors or variables that can change in the experiment
2. Gather all necessary materials and equiptment
3. Design the procedure
4. Conduct the experiment
5. Collect & Analyze data

Make sure your experiment is controlled!

• When setting up an experiment, we only want to change ONE variable or factor at a time.
• For example, if I am testing if my dogs bark more at a stranger or an unfamiliar sound, I am going to test each one of these factors separately.
• If I test both at the same time, we are not going to be able to tell which one made my dogs bark more.

Test both separately!

Sample Experiment Procedure:

Test both separately!

How will you record results?

• Data is information that is collected or analyzed in an experiment.
• It can be presented in graphs, charts, tables, pictures, and many more ways.
• The data that I would collect in my experiment would be the number of times my dog barks.
• I would record this data in a table that looks like this:

My example Procedure:

• Materials:
• dog, a stranger, a speaker, timer, and notebook.

• Procedure:

1. I would go to a quiet place.
2. The stranger would approach from a distance
3. I would observe and count the number of barks.
4. I would record these results on my table.

• I would repeat the procedure, and use an unfamiliar sound instead of a stranger.

Step 5: Analyze Data

• Use the data you gathered to decide if your hypothesis was supported or not.

• Does the data from the graph support the idea that "If a dog sees a stranger, it will bark more than when it hears an unfamiliar sound?"

Step 6: Draw a Conclusion From Your Data

• If the data supports your hypothesis, test again!
• More trials make results more reliable.

• If your data does NOT support your hypothesis, revise and try again.
• Many studies take a lot of trial and error and it can take years to publish a study.
• Revising is part of science in action!

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