1. Scientific Method
How Scientist Work

2. Types of Science Inductive Reasoning
Begins with specific observations & leads to theory
Scientific method
Deductive Reasoning
General to specific
Begin with theory & work towards hypothesis

3. Explaining the Evidence
Once evidence has been interpreted, scientist try to explain it.
A hypothesis is a possible explanation for a set of observations OR an answer to a scientific question.
A prediction can be made from a hypothesis. “If________, then ____” statement.

4. How Scientist Work Designing an experiment involves several steps.
Observations
Questions
Background/research
Hypothesis (prediction)
Experimentation
Conclusions
An experiment must be replicated to support findings.

5. Examples of hypothesis
Good
Plants will grow taller when given Miracle Grow.
Girls will score higher on math tests than boys.
Hermit crabs choose colorful shells over non- colored shells.
Bad
Plants will grow better when given Miracle Grow.
Girls are smarter than boys.
Hermit crabs like colorful shells.

6. Sample Questions Do crickets prefer light or dark?
Will ice sink in water?
Which will a nail rust faster in?  Salt water or tap water?
Do earthworms prefer their soil moist or dry?

7. Experimenting A controlled experiment involves 2 groups.
Experimental Group
Observes or measures independent variable (manipulated variable). This is the ONE factor that is changed in the experiment.
Control Group
Observes or measures dependent variable (a.k.a. responding variable). These are factors that do not change in the experiment.

8. Example of an Experimental Design
Hypothesis: Plants will grow taller when given Miracle Grow.
Plants A & B are both given the same amount of light, water, and are stored at the same temperature. Plant A is given Miracle Grow.
All the variables are kept constant except the one you are testing.
Independent Variable - the factor you change, what you do to your exp. group. (Miracle Grow)
Dependent Variable - what happens as a result of that treatment, what you are measuring (height of plant)

9. Collecting Data/Evidence
A scientist carefully collects and organizes data from the experiment.
Data should always be presented in a neat fashion, usually tables or graphs.
NO OPINION!

10. Conclusion Summarize your finding using evidence from experiment.
Was your hypothesis correct/refuted?
What are possible errors in experiment?
What conclusions can you make based on data table/graphs?

11. Development of a Theory
A theory is a well tested and supported hypothesis.
Theories must explain a wide range of observations.
Theories can be changed if new evidence presents itself .

12. Flow Chart

13. Types of Observations Qualitative Quantitative
Descriptive data using five sense (smell, taste, touch, hear, see)
The leaf is green
The wool is soft
Quantitative
Measurable data such as weight, volume, density.
The plant height is 5.3 cm
The density of water is 1.0g/mL