SCIENTIFIC METHOD

15 sec to get in groups of 4 Use whiteboards to write scientific method 10 min Look at other boards, add to your whiteboard if need to 3 min

SCIENTIFIC METHOD---LIST STEPS

Sci method song:

OBSERVATION ACTIVITY CANDY: Write list of observations Observation Game PENNY: Write list of observations using all senses. Use hand lens if you need to. Compare list with partner. Any observations that you can make with numbers? Quantitative VS Qualitative Why do we need both? What are some issues?

TYPES OF DATA Observation: receiving knowledge of the outside world through our senses, or recording information using scientific tools and instruments Qualitative: describe the quality ex: color, luster, taste, smell, etc. Quantitative: measuring the quantity ex: height, mass, volume, length, temp, etc.

OLD-TIME STANDARDS Measure objects using early kinds of standards. Use early standards to measure the following objects: 1. Your palm in digits 2. your span in palms 3. Your cubit in spans 4. the length of a pen in digits 5. The length and width of in palms How do the measurements compare with those of your classmates? Why is important to standardize units so that everyone uses the same ones? PALM: SPAN: CUBIT: DIGIT: finger’s breadth/width (ancient Egypt)

METRIC SYSTEM Meter: Length Liter: Volume Grams: Mass 1. 3km= m 2. 4g= cg 3. 5ml= l

METRIC SYSTEM Practice

OBSERVATION OR INFERENCE? Inference: conclusion reached on basis of evidence and reasoning EX: classroom door unlocked, hot coffee on desk, lights are on Difference between observation and inference?

DIFFERENCE BETWEEN OBSERVATION AND INFERENCE? Prediction: a guess what might happen based on observations Look at pictures again and make predictions What are you basing your predictions on?

5 observations 5 inferences 5 predictions Write on board

Observations InferencesPredictions

PREDICTION VERSUS HYPOTHESIS Hypothesis: a tentative explanation for a observation or problem that can further be tested by experimentation What is the difference? A prediction is basically an attempt to "guess" what will happen next. A hypothesis, on the other hand, establishes a relationship, which helps explain what happens.

HERE ARE THE STEPS TO FORM A HYPOTHESIS: Think about any observations or previous knowledge you know about the variables. Express what you think will be the effect of changing one of the variables (Independent variable) on the other variable you expect to change (Dependent variable). Develop your hypothesis using a statement. If the (independent variable) ( describe how you would change it), then the (dependent variable ) will (describe the effect)

VARIABLES Independent variable: What you have control over, what is being changed/manipulated Dependent variable: What you measure in an experiment/what is affected Controlled variable: is constant, stays the same Example: You are interested in how stress affects heart rate in humans. Your independent variable would be the stress and the dependent variable would be the heart rate. You can directly manipulate stress levels in your human subjects and measure how those stress levels change heart rate.

IDENTIFYING INDEPENDENT, DEPENDENT, CONTROL VARIABLES At study was done to find if different tire treads affect the braking distance of a car Students of different ages were given the same puzzle to assemble. The puzzle assembly time was measured. An experiment was performed to determine how the amount of coffee grounds could affect the taste of coffee.

IDENTIFY INDEPENDENT, DEPENDENT, AND CONTROL VARIABLES. How do the different chemicals in fertilizers affect plant growth? How long does it take three different types of enzymes to digest a liter of milk? Researchers want to discover if listening to classical music helps students earn better grades on a math exam. Researchers are interested in seeing how long it takes people to respond to different sounds. Researchers want to know whether first-born children learn to speak at a younger age than second-born children.

PRACTICE WRITING A HYPOTHESIS Independent Variable: baseball batting practice Dependent Variable: batting average Hypothesis: If batting practice increases, then the batting average will increase. Independent Variable: depth of Lake Powell Dependent Variable: water temperature Hypothesis:

PRACTICE WRITING A HYPOTHESIS Independent Variable: Number of recycling posters Dependent Variable: Amount of aluminum cans in recycle bins Hypothesis: Work with Partner: Independent Variable: Dependent Variable: Hypothesis:

RELATIONSHIP BETWEEN OBSERVING, INFERRING, AND HYPOTHESIZING Observation: there are fleas on dogs Inference: golden retrievers have more flea habitat than Chihuahuas Variables: size of dog and flea population Hypothesis: If dogs are larger, then they will have a larger flea population than smaller dogs. Work with partner: Observation: Inference: Variables: Hypothesis:

Scientist 1Scientist 2Scientist 3 Observation Fact Hypothesis Theory Law

Scientist 1Scientist 2Scientist 3 ObservationLead to factsData FactAre observations, Don’t explain ObservationsObservation HypothesisTestable statement, Look at relationships, Help build theories Lead to theoriesExplains how something works AFTER facts are gathered, needs to be testable, provides evidence for or against TheoryExplanation, testedExplains observations, lasts the test of time A Body of knowledge that explains a major hypothesis LawDescriptive generalization Reduced to an equation LAW: describes some aspect of the universe ****Theories do NOT always become Laws

Ecology: Hypothesis pg Read pg 24---write notes about theories in science