The Scientific Method

The Scientific Method-The steps taken in a specific order to get an answer to a

posed problem.

Steps of the Scientific Method1.Problem2.Hypothesi

s3.Experime

nt4.Results5.Conclusio

n

Step 1: Identify the Problem

• Using observations, identify a problem you would like to solve.o Observations are done with your

five senses to gather information.

o Ask questions that lead to a problem.

Step 1: Identify the Problem• Two types of observations:–Quantitative observations—deal

with numbers• Ex. 100 degrees outside

–Qualitative observations—deal with a description• Ex. Its hot outside.

Step 2: Develop a Hypothesis

• A hypothesis is a possible answer to a scientific question.oNot a fact (prediction)oBased on observations and knowledge

oMust be testable

Step 2: Develop a Hypothesis

• Write your hypothesis using your variables (what is changing)

• Hypothesis Format:–“If (what is changing on purpose)

then (what is changing due to what you already changed) because…

• “If ______________________then ____________

________________ because…

Step 2: Develop a Hypothesis• Example:

Question: How does the amount of salt affect the temperature where water boils?Hypothesis: If there is more/less (circle one) salt then water will boil at a higher/lower (circle one) temperature because _____________________________.

A scientist wants to know if water boils at a higher temperature when salt is added. Here is their experiment:

One Quart of Boiling Water

with

NO SALT

One Quart of Boiling Water

with

TWO TABLESPOONS

OF SALT

One Quart of Boiling Water

with

FOUR TABLESPOONS

OF SALT

Step 2: Develop a Hypothesis• Example:Maria is from planet DontKnowALot. She is doing an experiment. She has three people in her experiment.

Maria will measure the amount of weight that each person gains after a month.Question: How does the type of liquid affect how much weight a person gains?Hypothesis: If _________________________________________,then _______________________________________________because _____________________________________________.

Person 1 will drink only water.

Person 2 will drink only juice.

Person 3 will drink only Coca Cola.

Independent Practice:

• Complete Figure 2 on developing a hypothesis.

The Scientific Method

Step 3: Test the Hypothesis

• Materials:• A list of all

the things you need

• Procedure• Step by step

instructions• Identifies the

variables used in the experiment

Testing the hypothesis is simply conducting the experiment (materials and procedure.

Step 3: Test the Hypothesis

Variables- factors that can change in an experiment, must be the same.

Variables Video

Step 3: Test the Hypothesis

Independent Variable- the one variable that is purposely changed to test a hypothesis

Step 3: Test the Hypothesis

Dependent Variable-the factor that may change in response to the independent variable

Step 3: Test the Hypothesis

Controlled Experiment-an experiment in which only one variable is changed at a time

Guided Practice:

Which people in the experiment are in the control group?

Guided Practice:

What are the independent and dependent variables? Explain.

Guided Practice:

What should Mr. Krabb’s conclusion be?

Why is Group B reporting feeling better?

Independent Practice:

• Complete worksheet on conducting an experiment.

The Scientific Method

Step 4: Results

Collecting data is writing down the results of the experiment.

Data should be recorded in a table.

Step 4: ResultsData- are the facts, figures, and

other evidence gathered through qualitative and quantitative

observations.

Step 4: Parts of a Graph

Guided Practice:• With your partner, use the data below to create a graph.Height of the Plant

by Day with Fertilizer

Day Height (cm)

1 152 183 23 4 24 5  21

Guided Practice: Graphing

The Scientific Method

Step 5: ConclusionA conclusion is a summary of what

you have learned from an experiment.

Ask yourself: Does my data support my hypothesis?

Step 5: ConclusionCommunicating is the sharing of ideas and results with others through speaking and writing.

Before an experiment is published other scientists must test it for accuracy.

Step 5: Conclusion

Scientific theory- a well-tested and widely accepted explanation of observations and experimental results.

Step 5: ConclusionScientific law-describe observed patterns in nature without trying to explain those patterns.