Scientific Method… …It’s how we think about the world around us… It’s not just for geeks!!

Scientific Method is… An organized approach to asking questions and making discoveries. The way that scientists (and many non- scientists) think about problems that they encounter.

Science is nothing more than a refinement of everyday thinking.

The Steps of Scientific Method: 1. Observation 2. Problem 3. Hypothesis 4. Experiment 5. Data 6. Conclusion 7. Theory

One dumb but effective way to remember Scientific Method!!! Our Pizza Has Extra Delicious Cheesy Toppings  Observation  Problem  Hypothesis  Experiment  Data  Conclusion  Theory

1. Observations: or Information gathered using the five senses or tools

Problem: A question one might ask based on the observations that are made.

Hypothesis A possible explanation of the problem that we wish to test. (it doesn’t have to be correct!!) Many hypotheses can be made – they predict the outcome of an experiment.

Experiment An organized test of a hypothesis. SUPERCOOLING EXPERIMENT: In this experiment, we super-cooled ultrapure water to -21C / -6F and pour it into a very cold bowl. It pours out as a liquid and turns to slush, forming ropelike peaks. link

Data The results of experiments. Data can be expressed as numbers or descriptions. Example: the elephant is 3 meters tall. Example: Mrs. Agar loves onions!

Conclusion What has been learned from the experiment. Conclusions are supported by data. We can conclude that Mr. Corey is officially the funniest and best looking Biology teacher!!! Data supports this.

Theory A broad explanation of natural events that is strongly supported by a body of evidence - time tested by many people. Example: The theory of gravity.

Some other scientific method terms… Inference – a possible explanation based on an observation. ex) Mr. Corey likes science. Opinion – What someone thinks about something. We try to keep this out of science! ex) Only losers watch “The Biggest Loser”

Some other scientific method terms… Variable – that which is manipulated in an experiment to get a result. Independent Variable – When this changes, it results in change in the other variable. example- covering/not covering the meat Dependent Variable - That which changes as a result of a change in the ind. Variable. example – getting maggots or not getting maggots

Some other scientific method terms… Control – What we compare our data against. (usually helps to show what we already know) example – leave meat out uncovered: maggots form on meat.

Validity: What makes a good experiment? Question- what is the average vertical leap of an HFL bio. Student? A good experiment should: Be easily repeatable Be Unbiased – don’t expect a certain result…(don’t only test basketball players!) Control for variables – footwear, sex of subjects, last night’s athletic events, etc… Have an adequate sample size (number of subjects) Larger sample size = higher validity Only test one question at a time.

The great backpack experiment… You have observed many students with large, overfilled backpacks…(wait ‘til you get your biology book!)…also, many backpack straps have been breaking. In the past, backpacks have been made of canvas. Many new backpacks are nylon. You want to know whether canvas or nylon backpacks break more when carrying a lot of books (25 lbs.) for a whole school day.

Design a backpack experiment! Form a hypothesis and design an experiment to test it. Make sure you use all steps of scientific method (except theory)…you can invent data. Make sure to have a control group, and design a “good experiment.”