Steps of the Scientific Method

The Scientific Method involves a series of steps that are used to investigate a natural occurrence.

We shall take a closer look at these steps and the terminology you will need to understand before you start a science project.

Formulate a Hypothesis Scientific Method Question Formulate a Hypothesis Experiment Observe and Record Analyze Results Share the Results

Steps of the Scientific Method 1. Question: Develop a question or problem that can be solved through experimentation. Ask yourself, “What do I want to learn? Or “I wonder what would happen if…”

Steps of the Scientific Method 2. Formulate a Hypothesis: Predict a possible answer to the problem or question. Make a guess and then answer… Example: If soil temperatures rise, then plant growth will increase.

Do you remember the next step?

Steps of the Scientific Method 3. Experiment: Test your hypothesis by conducting an experiment.

Steps of the Scientific Method 4. Observe and Record: Make careful observations and write down what happens.

Steps of the Scientific Method 5. Analyze Results: Use your information to draw conclusions about your experiment. Was your hypothesis correct?

Steps of the Scientific Method 6. Share the Results: Present your experiment, observations, and conclusions with others.

Do you think you can name all six steps?

Variables Variables: A factor in an experiment or scientific test that tends to vary, or take on different values, while other elements or conditions remain constant.

Independent Variable The independent variable is a factor that the experimenter intentionally changes.

Dependent Variable The dependent variable, or responding variable, is the factor that may or may not change due to manipulation. (The dependent variable is always the response or reaction to the independent variable).

How to Form a Hypothesis Using Variables If…. Independent variable Then…dependent variable Example: Independent Variable: I feed my cat a lot Dependent Variable: she will get fat *Remember….try to use INCREASE and DECREASE in your hypothesis! IF I increase the amount of food I give my cat, THEN she will increase her weight.

Do you know the difference between independent and dependent variables now?

(For example, environmental conditions). Control In a scientific experiment, a control is the variables that are not being studied that are held constant so they do not influence the experimental outcome. (For example, environmental conditions).

Can you think of some constants for an experiment?

Let’s Practice Independent and Dependent Variables Identify the variables in the following hypotheses. If I decrease the amount of diet cokes I drink a week, then my stomach will stop hurting. Independent Variable? Dependent Variable?

Let’s Practice Independent and Dependent Variables Identify the variables in the following hypotheses. If I increase the amount of time I read daily, the better I will be at school. Independent Variable? Dependent Variable?

Let’s Try Time Patrick SpongeBob Initial Amount 18 5 After 1 Week 24 9 Marshmallow Muscles Larry was told that a certain muscle cream was the newest best thing on the market and claims to double a person’s muscle power when used as part of a muscle-building workout. Interested in this product, he buys the special muscle cream and recruits Patrick and SpongeBob to help him with an experiment. Larry develops a special marshmallow weight-lifting program for Patrick and SpongeBob. He meets with them once every day for a period of 2 weeks and keeps track of their results. Before each session Patrick’s arms and back are lathered in the muscle cream, while Sponge Bob’s arms and back are lathered with the regular lotion. Which people are in the control group? What is the independent variable? What is the dependent variable? What should Larry’s conclusion be? Time Patrick SpongeBob Initial Amount 18 5 After 1 Week 24 9 After 2 Weeks 33 17

Try with a Partner Slimotosis Sponge Bob notices that his pal Gary is suffering from slimotosis, which occurs when the shell develops a nasty slime and gives off a horrible odor. His friend Patrick tells him that rubbing seaweed on the shell is the perfect cure, while Sandy says that drinking Dr. Kelp will be a better cure. Sponge Bob decides to test this cure by rubbing Gary with seaweed for 1 week and having him drink Dr. Kelp. After a week of treatment, the slime is gone and Gary’s shell smells better. What was the initial observation? What is the independent variable? What is the dependent variable? What should Sponge Bob’s conclusion be?

Qualitative Characteristics This is describable. (Example: how something looks, feels, smells, tastes, sounds, etc.)

Quantitative Measurement This is measurable. Examples: degrees, feet, numbers

Observe your world and come up with a question to answer using the Scientific Method!