Scientific Method – What is it? An orderly approach to learning information and solving problems

Why Use the Scientific Method? Some people say that spinach is good for you

Why Use the Scientific Method? Some people say that students need at least 10 hours of sleep to learn better in school.

Why Use the Scientific Method? Some people say that students who listen to their ipod when they study get bad test scores.

Why Use the Scientific Method? Are YOU going to believe them???

Why Use the Scientific Method? Are YOU going to believe them??? The Scientific Method is a logical way to solve problems. It is a method of conducting an experiment in order to test ideas like these to see whether or not they are true.

Why Use the Scientific Method? *Consistent *Clear *Simple *Repeatable *Thorough *Scientists have to and you do too!

Steps of the Scientific Method 1.Problem 2.Research 3.Hypothesis 4.Procedure 5.Experiment 6.Record and Analyze Data 7.Conclusion

Problem Must be stated as a question.

Problem Examples Must be stated as a question. *What will happen if I put my hand in a bucket of ice water for four minutes? *What happens to a houseplant if it is not watered for three weeks? *What happens to a person’s heart rate if that person runs a mile?

Research Important step often skipped. Do Research BEFORE making a hypothesis. Hypothesis = EDUCATED guess. Research so you know what you are talking about!

Research Examples of Research: Books On-line Observations

The Hypothesis *An educated guess *Answers the question in the problem *Written in “If, then, because” form *Based on past observations or scientific knowledge from research If, then, because

The Hypothesis “If, then, because” format How it fits into your experiment –If I do something –Then something will happen –Because (the research) If, then, because

From Problem to Hypothesis *IF I put my hand in a bucket of ice water for four minutes, THEN my hand will hurt, BECAUSE the cold will make my blood vessels get smaller, which will cause less blood to go to my hand, and make my hand hurt. If, then, because Problem: *What will happen if I put my hand in a bucket of ice water for four minutes? Research: When blood vessels get very cold, they get smaller, and the blood can’t flow through them, causing pain.

*IF I put my hand in a bucket of ice water for four minutes, THEN my hand will hurt, BECAUSE the cold will make my blood vessels get smaller, which will cause less blood to go to my hand and make my hand hurt. If, then, because Terrific Hypothesis

From Problem to Hypothesis If, then, because Problem: *What happens to a houseplant if it is not watered for three weeks? Research: Plants soak up water from their roots and then lose water through their leaves in a process known as transpiration. Hypothesis: *IF a houseplant is not watered for three weeks, THEN the plant will wither and droop BECAUSE the water will leave the plant through the leaves and make the plant droopy.

If, then, because *IF a houseplant is not watered for three weeks, THEN the plant will wither and droop BECAUSE the water will leave the plant through the leaves and make the plant droopy. Terrific Hypothesis

From Problem to Hypothesis Hypothesis: *IF a person runs a mile, If, then, because Problem: *What happens to a person’s heart rate if that person runs a mile? Research: When we exert our bodies, they require more oxygen, so our heart pumps harder in order to get more oxygen to all the cells of our bodies. THEN his or her heart rate will increase, BECAUSE more oxygen is needed at the cells.

If, then, because Terrific Hypothesis *IF a person runs a mile, THEN his or her heart rate will increase, BECAUSE more oxygen is needed at the cells.

Variables A variable is a factor that changes the outcome of the experiment 3 Types –*Independent variable: the ONE AND ONLY thing that is being changed (manipulated) in an experiment –*Dependent variable: what changes as a result of manipulating the independent variable –*Constant variables: all of the factors that must stay the same in both set-ups. Used to isolate the independent variable so you are only testing for one thing.

Hypothesis and Variables If (I do something), then (I expect something to happen), because (research) If, then, because Linking the Variables to the Hypothesis

Hypothesis Format If (I do something) (Independent Variable), then (something will happen) (Dependent Variable), because (Research) If, then, because Linking the Variables to the Hypothesis

From Problem to Hypothesis to Variables Hypothesis: *IF I put my hand in a bucket of ice water for four minutes, THEN my hand will hurt, BECAUSE the cold will make my blood vessels get smaller, which will cause less blood to go to my hand, which will make my hand hurt. If, then, because Problem: *What will happen if I put my hand in a bucket of ice water for four minutes? Independent Variable: Dependent Variable: Constants: Temperature of environment of the hand Pain level Don’t do anything else to the hand

Hypothesis Stations Soon you and a partner are going to move around to 5 different Hypothesis Stations. Your task is to: 1.Read the problem and the research 2.Write a good IF, THEN, BECAUSE hypothesis 3.Write the independent variable 4.Write the dependent variable 5.Write the constants Lets do 2 more for practice before you get started

From Problem to Hypothesis to Variables If, then, because Problem: *What happens to a houseplant if it is not watered for three weeks? Research: Transpiration Independent Variable: Dependent Variable: Constants: Amount of water given to plant The condition of the plant Type of plant, Amount of sunlight, Type of soil, Hypothesis: *IF a houseplant is not watered for three weeks, THEN the plant will wither and droop BECAUSE the water will leave the plant through the leaves and make the plant droopy.

From Problem to Hypothesis to Variables If, then, because Problem: *What happens to a person’s heart rate if that person runs a mile? Independent Variable: Dependent Variable: Constants: Amount of activity a person is doing What happens to the heart rate Age of the person, physical condition of the person Hypothesis: IF a person runs a mile, THEN his or her heart rate will increase, BECAUSE more oxygen is needed at the cells.

Hypothesis Stations Time to break into groups of 2 – 3 and go to the Hypothesis Stations 1.Read the problem and the research 2.Write a good IF, THEN, BECAUSE hypothesis 3.Write the independent variable 4.Write the dependent variable 5.Write the constants Click here for Hypothesis Station WorksheetHypothesis Station Worksheet

Station #1 Problem: What effect does high temperature have on radish germination? Research: Growing radishes in high temperatures causes the leaves to grow thick and the fruit to grow small.

Station #1 Hypothesis: If I grow radishes in a high temperature, then the radishes will be smaller, because high temperatures make the leaves big and the fruit small. Independent Variable: Temperature Dependent Variable: Size of the fruit Constants: Type of plant, soil, water, light, fertilizer

Station #2 Problem: What effect does studying with music have on student test scores? Research: Listening to classical music while studying helps the brain create neurons which causes the body to relax, which causes better test scores.

Station #2 Hypothesis: If students listen to classical music while they study, then their test scores will increase, because classical music helps the brain create neurons and the body to relax. Independent Variable: Listening to classical music Dependent Variable: Test scores Constants: Amount of sleep, eating the right foods

Station #3 Problem: What effect does food color have on the amount of food fish eat? Research: Fish are more attracted to brightly colored objects.

Station #3 Hypothesis: If I feed my fish brightly colored food, then they will eat more, because fish are attracted to brightly colored objects. Independent Variable: Color of fish food Dependent Variable: Amount of food the fish eats Constants: Type of fish, type of food, temperature of water

Station #4 Problem: What effect does light have on plant growth? Research: Plants need light to perform photosynthesis and create their food.

Station #4 Hypothesis: If I put my plant in light, then it will grow, because plants need light to perform photosynthesis. Independent Variable: Amount of light the plant receives Dependent Variable: Growth of plant Constants: Type of plant, soil, water, fertilizer

Station #5 Problem: What effect does smiling at the teacher have on the teacher giving no homework? Research: Happy students make happy teachers and happy teachers give less homework.

Station #5 Hypothesis: If we smile at the teacher, then we will not have homework, because happy students make happy teachers and happy teachers give less homework. Independent Variable: Smiling at the teacher Dependent Variable: Amount of homework Constants: Same students, same hour, same level of respect

Steps of the Scientific Method 1.Problem 2.Research 3.Hypothesis 4.Procedure

Procedure 2 Parts

Procedure Materials *List of items needed to complete the lab *Amounts of materials needed Procedure Step by step directions to do lab Can be repeated by someone else

Procedure Materials *List of items needed to complete the lab *Amounts of materials needed Materials List Example ½ liter of salt Triple beam balance One sheet of loose-leaf paper 500 ml beaker 300 ml water 1 Egg

Procedure Step by step directions to do lab Can be repeated by someone else Procedure Example 1.Fill beaker to 300 ml mark with water. Add salt ONE GRAM at a time. 2.After each addition of salt, put the egg in the beaker to see if it floats. 3.Remove the egg before adding more salt. 4.When the egg floats, record the number of grams required for your egg to float. 5.If you have additional time, complete another trial following the same steps.

Procedure Materials *List of items needed to complete the lab *Amounts of materials needed Procedure Step by step directions to do lab Can be repeated by someone else Write a GOOD PROCEDURE to make a peanut butter and jelly sandwich.

Procedure The Procedure must be specific and repeatable.

Steps of the Scientific Method 1.Problem 2.Research 3.Hypothesis 4.Procedure 5.Experiment

Experiment Two setups for the Experiment – –Control set-up and –Experimental set-up –(so you can compare results) ALL variables are the same in BOTH set-ups except –the independent variable in the experimental is changed or manipulated and –the variable in the control set-up remains the same. (THINK – the CONTROL stays THE SAME )

Experimental and Control Set-Ups Problem: Will I lose weight if I eat fish 3 times a week? Research: Eating fish helps you lose weight. Hypothesis: If I eat fish 3 times a week, then I will lose weight, because eating fish helps you lose weight. Set-Ups: Experimental: Eating fish 3 times a week Control: Eating your normal diet without eating fish IV: Eating fish DV: Weight loss Constants: Same amount of exercise, same breakfast and lunch, same amount of sleep.

Collect Data Make Observations! –2 Types of Observations Qualitative Data: THINK Quality  a description that uses your senses Sight, smell, taste, touch, hearing Quantitative Data: THINK Quantity  Quantity = NUMBER  measurements uses scientific instruments

Qualitative Data Your five senses: touch, sight, smell, hearing, taste

Quantitative Data Instrument Metric To Measure to UseBase Unit LengthRulerMeter (m) AreaRulerSquare meter (m 2 ) Volume (solid)Ruler Cubic meter (m 3 ) Volume (liquid)BeakerLiter (L) MassBalanceKilogram (Kg) TemperatureThermometerCelsius ( C)

Collect Data Enter Data in a Data Table –Quantitative Must have Units –Qualitative BrightnessSound Light Bulb #1BrighterLouder Light Bulb #2DimmerQuieter ControlNormal

Analyze Data Use data in your table to make graphs Bar ChartLine Chart Line Chart = TIME

How to Graph Data in an Experiment

IF I do something THEN something will happen If, then, because Linking the Hypothesis to the Graph How to Graph Data in an Experiment

IF I do something THEN something will happen If, then, because Let’s work together to graph some possible results Graphing Partners Click here for handout

Problem #1 Hypothesis: If I grow radishes in a low temperature, then the radishes will be bigger, because high temperatures make the leaves big and the fruit small. Independent Variable: _________________________ Manipulating IV: ________________________ _________________________ Control Variable: ________________________ Dependent Variable: Size of fruit Constant Variables: Type of plant, soil, water Title: __________________________________ IV: __________________________________ DV: ________________________________ Unit: _____________

Problem #1 Hypothesis: If I grow radishes in a low temperature, then the radishes will be bigger, because high temperatures make the leaves big and the fruit small. Independent Variable: temperature Manipulating IV: low temperature Control Variable: regular temperature Dependent Variable: Size of fruit Constant Variables: Type of plant, soil, water Title: __________________________________ IV: __________________________________ DV: ________________________________ Unit: _____________

Problem #1 Hypothesis: If I grow radishes in a low temperature, then the radishes will be bigger, because high temperatures make the leaves big and the fruit small. Independent Variable: temperature to grow Manipulating IV: low temperature Control Variable: regular temperature Dependent Variable: Size of fruit Constant Variables: Type of plant, soil, water The Effect of Temperature on Radish Growth IV: Growing Temperatures DV: Size of Radish Fruit Unit: cm Low Temperature RegularTemperature

Problem #2 Hypothesis: If students listen to classical music while they study, then their test scores will increase, because classical music helps the brain create neurons and the body to relax. Independent Variable: _________________________ Manipulating IV: ________________________ _________________________ Control Variable: ________________________ Dependent Variable: Test Scores Constant Variables: Amount of sleep, eating right foods Title: __________________________________ IV: __________________________________ DV: ________________________________ Unit: _____________

Problem #2 Hypothesis: If students listen to classical music while they study, then their test scores will increase, because classical music helps the brain create neurons and the body to relax. Independent Variable: listening to music Manipulating IV: classical music Control Variable: no music Dependent Variable: test scores Constant Variables: Amount of sleep, eating right foods Title: __________________________________ IV: __________________________________ DV: ________________________________ Unit: _____________

Problem #2 Hypothesis: If students listen to classical music while they study, then their test scores will increase, because classical music helps the brain create neurons and the body to relax. Independent Variable: listening to music Manipulating IV: classical music Control Variable: no music Dependent Variable: test scores Constant Variables: Amount of sleep, eating right foods The Effect of Classical Music on Test Scores Studying with or without Music Score on Test Unit: % Correct Classical Music No Music

Problem #3 Hypothesis: If I put my plant in light, then it will grow, because plants need light to perform photosynthesis. Independent Variable: _________________________ Manipulating IV: ________________________ _________________________ Control Variable: ________________________ Dependent Variable: _______ _________________________ Constant Variables: _________ _________________________ Title: __________________________________ IV: __________________________________ DV: ________________________________ Unit: _____________

Problem #3 Hypothesis: If I put my plant in light, then it will grow, because plants need light to perform photosynthesis. Independent Variable: light Manipulating IV: light Control Variable: no light Dependent Variable: Growth of plant Constant Variables: Type of plant, soil, water Title: __________________________________ IV: __________________________________ DV: ________________________________ Unit: _____________

Problem #3 Hypothesis: If I put my plant in light, then it will grow, because plants need light to perform photosynthesis. Independent Variable: light Manipulating IV: light Control Variable: no light Dependent Variable: Growth of plant Constant Variables: Type of plant, soil, water The Effect of Light on Plant Growth IV: Type of Light DV: Growth of Plant Unit: cm Light No Light

Conclusion State your results Did your experiment... prove your hypothesis OR not prove your hypothesis

Writing your Conclusion 1. Restate problem and hypothesis 2. Explain what happened to the dependent variable when you changed the independent variable 3. Answer the question in the problem –provide evidence from your data –compare the control to the independent variable 4.Was the hypothesis proved or not proved? 5.Why or why not? 6.What kind of errors could you have made that might have affected your data? 7.What would you do differently next time?

The Conclusion: Example The purpose of this lab was to find out what happens to a person’s heart rate as that person increases his or her activity level. My hypothesis was that if a person increases his or her activity level, then that person’s heart rate will increase because their cells need more oxygen to keep working. The variable was the amount of activity the person was doing. I found out that my hypothesis was proved because when the members of my group went from resting to walking, and then walking to running, their heart rate went up each time. For example, I went from 77 beats/min resting to 86 beats/min walking, and then up to 103 beats/min running. My other group members had similar results. Therefore, I conclude that when a person increases his or her activity level, that person’s heart rate will also increase.

Steps of the Scientific Method 1.Problem 2.Research 3.Hypothesis 4.Procedure 5.Experiment 6.Record and Analyze Data 7.Conclusion

Brain Pop eofscience/scientificmethod/index.wemlhttp:// eofscience/scientificmethod/index.weml eofscience/scientificproblemsolving/ eofscience/scientificproblemsolving/

Now you’re all ready to use the scientific method in your own labs! Let’s get going!

*INDEPENDENT VARIABLE: temperature of environment in which hand is located *INDEPENDENT VARIABLE: amount of water given to a plant *INDEPENDENT VARIABLE: amount of activity the person is doing Independent Variable Examples