Scientific Method

Think about this situation:You observe that in the morning when your baby brother cries, your puppy starts to howl. Later in the day, a policeman outside your house blows a whistle and your puppy howls again. Then next day, your sister practices her piano lesson and as she plays high-pitched notes, your puppy starts howling again.

How can you explain your puppy howling? What evidence could you use to support your explanation?

Step 1: Make observations, then

state your problem or question

This is the problem you want to solve or question you want answeredAlso called the “purpose”

Example: Why is my puppy howling?

Step 2: Research your topic.

Collect information about your topicUse different research sources such as books, magazines, interviews, and observations Can give you ideas for an experimentEx: Research dogs...

Step 3: Form a Hypothesis.

“Educated” explanation Must be a testable answer to your questionShould be stated in “If. . .then . . . FormatExample: If there is a high pitched sound, then my puppy will howl.

Step 4: Design a controlled

experiment. Tests the hypothesis under certain conditions Control group: group not being tested, used for comparison Independent (Manipulated) variable: variable you are testingDependent (Responding )variable: resulting variable, what you see happening, what you record data about

What kind of experiment could you perform with your puppy?

Step 5Record/analyze data.

record information from experimentQuantitative, or qualitative (next slide definition)May be arranged in table, graphs, journals, etc. Example: What kind of data would we have for our experiment?

Types of Observations (Data that you collect.)Quantitative (Quantitative (numbersnumbers). 28 ). 28

students, 1.5 meters, 2 mL, etc.students, 1.5 meters, 2 mL, etc.

Qualitative (Qualitative (descriptionsdescriptions). Short, ). Short, tall, small, red, smooth, etc.tall, small, red, smooth, etc.

Step 6: Form conclusion.

Analyze data and determine if hypothesis was correctRecap the experimentConclusion may be confirmed only after many trials show the same resultIf well supported over time, may be referred to as a “theory”Theory: well tested explanation that brings together a broad range of observations

Test Yourself:

A. Conclusion C. Data E. Hypothesis

B. Control group D. Experimental group F. Problem

1. A chart with the number of roaches killed and the treatments they received.

2. I wonder what will kill a roach?

3. Roaches are killed more quickly when sprayed with Raid than if sprayed with water.

4. One group of roaches is sprayed with Raid, another is sprayed with water.

5. If roaches are sprayed with Raid, then they will die quickly.

6. One group of roaches is not sprayed with anything.