I have noticed some things…Using the scientific method

My observations were…

•All scientific questions and studies start here!

•I have noticed a lot of students chewing things like gum, candy, or sunflower seeds.

Observations vs. InferenceObservations Inferences

• Using your senses or a tool to record an event, characteristic, or behavior

• NO BIAS

• Example:

• A logical conclusion drawn from observations and prior knowledge

• Example:

Qualitative vs. Quantitative Observations

Qualitative

• A measured observation

• Example: Miss Smith is 162 cm tall.

• A useful, descriptive observation

• Example: the substance in the flask is giving of a pungent odor

Quantitative

My Problem (Question)

•Scientific questions must be able to be answered by observations and gathering evidence▫ questions come from observations

▫ must be testable through experimentation, survey or research▫ Deal with the natural world▫ Be genuine, something we don’t already know the answer to

•How many chews does it take to finish a tootsie roll?

Some information I know..

•Gather information & do research

•They are kind of difficult to chew•They are a little thick

My hypothesis

•A possible explanation for your problem or questions

•Not a fact•Must be testable•“If…., Then…” statements

•If tootsie rolls are difficult to chew, then it will take 50 chews to finish one tootsie roll.

My experiment• Must have clear steps• Must be controlled- only change 1 variable at a time• Variable- factors that can change in an experiment

▫ Independent- the 1 factor you change ▫Dependent- factor that may change in response to

independent variable▫Contstants- factors that remain the same

• Must have a control group- nothing is changed so you can compare your results

• Count how many chews it takes to finish a tootsie roll

Next step, Collect Data

•Tables should be created before you begin•Facts and figures gathered through

observation and experiment•graphs

Conclusions

•Summary of what you found•Did my results support or refute my

hypothesis?

•What’s next?!•Need more tests!

•Why?

Do your results support your hypothesis?•Test again to get more support

Do your results disprove your hypothesis?•Re-work or re-write your hypothesis and

continue through steps from there

Theory vs. Law• Theory – well tested,

repeatable hypothesis that attempts to answer WHY- ACCEPTED AS TRUE UNTIL PROVEN OTHERWISE

***Not always true or proven.

Example: Theory of Evolution

• Law- A statement meant to DESCRIBE an action or set of actions

***Proven to be true ALL the time

• Example: Newton’s 1st Law of Motion- an object at rest stays at rest unless acted upon by an outside force

Sample Experiment3. Test the Hypothesis – Example of a Test

▫ Experimental Scenario: Ms. Freeman and Ms. Dowd wanted to determine if there was a correlation between eating a nutritionally balanced breakfast and success on tests. One group of students was given a healthy breakfast and another group ate their normal breakfast before a test. They found that 7 out of 10 students who ate the healthy breakfast scored 80% or better on tests while 5 out of 10 students who ate their regular breakfast scored 80% or better on tests.

▫ Identify the following from the above experimental scenario: Independent Variable: ___________________________________ Dependent Variable: ____________________________________ Controlled Variables: ____________________________________ Control Group: ________________________________________ Experimental Group: ____________________________________