I have noticed some things Using the scientific

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. Inference Observations Inferences • Using your senses or a tool to record an event, characteristic, or behavior • A logical conclusion drawn from observations and prior knowledge • NO BIAS • Example:

Qualitative vs. Quantitative Observations Quantitative Qualitative • A measured observation • A useful, descriptive observation • Example: Miss Smith is 162 cm tall. • Example: the substance in the flask is giving of a pungent odor

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 1 st Law of Motion- an object at rest stays at rest unless acted upon by an outside force

Sample Experiment 3. 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: __________________