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.

• 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?"

Step 1: Make an Observation

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

• 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?"

Step 2: Ask a Question

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

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."

• 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.

Step 3: Form a Hypothesis

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

• 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

Step 4: Set up an Experiment

Test both separately!

• 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.

Make sure your experiment is controlled!

Test both separately!

Sample Experiment Procedure:

• 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:

How will you record results?

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.

• 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 5: Analyze 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!

Step 6: Draw a Conclusion From Your Data

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