The Scientific Method

The Scientific Method involves a series of steps that are used to investigate a natural occurrence.

We shall take a closer look at these steps and the terminology you will need to understand before you start a science project or do a laboratory exercise.

Problem/Question Observation/Research Formulate a Hypothesis Experiment Collect and Analyze Results Conclusion Communicate the Results

Steps of the Scientific Method Problem/Question Problem/Question: Develop a question or problem that can be solved through experimentation.

Steps of the Scientific Method Observation/Research Observation/Research: Make observations and research your topic of interest.

Steps of the Scientific Method Formulate a Hypothesis Formulate a Hypothesis: Predict a possible answer to the problem or question. Example: If soil temperatures rise, then plant growth will increase.

Steps of the Scientific Method Experiment Experiment: Develop and follow a procedure. Include a detailed materials list. The outcome must be measurable.

Steps of the Scientific Method Collect and Analyze Results Collect and Analyze Results: Modify the procedure if needed. Confirm the results by retesting. Include tables, graphs, and photographs.

Steps of the Scientific Method Conclusion Conclusion: Include a statement that accepts or rejects the hypothesis. Make recommendations for further study and possible improvements to the procedure.

Steps of the Scientific Method Communicate the Results Communicate the Results: Be prepared to present the project to an audience. Expect questions from the audience.

John watches his grandmother bake bread. He ask his grandmother what makes the bread rise. She explains that yeast releases a gas as it feeds on sugar (fermentation).

Problem/Question John wonders if the amount of sugar used in the recipe will affect the size of the bread loaf?

Caution with Terms Be careful how you use effect and affect. Effect is usually a noun and affect, a verb. “ The effect of sugar amounts on the rising of bread.” “How does sugar affect the rising of bread?”

Problem/Question Activity: Come up with a problem or question you might have in your own life. Answer these questions: 1)What materials are available? 2)What action can be observed? 3)What can I change to get a different action? 4)What ways can I measure a response to the change? Ex. My car won’t start

Problem/Question General topic: Plants Answer these questions: 1)What materials are available? Soil, Plants, Fertilizer, Water, Light/Heat, 2)What action can be observed? Plants grow 3)What can I change to get a different action? Plants spacing, kind, amount of water, location of hole 4)What ways can I measure a response to the change? Count the number of leaves, Measure the height, Weigh the fruit produced

Observation/Research John researches the areas of baking and fermentation and tries to come up with a way to test his question. He keeps all of his information on this topic in a journal.

Observation/Research Activity: Make a short list of the things you already know about that topic. Ex. 1.Cars need gas 2.Cars need electricity from the battery 3.Cars need oil

Formulate a Hypothesis

Hypothesis The hypothesis is an educated guess about the relationship between the independent and dependent variables.

Do you know the difference between the independent and dependent variables?

Independent Variable The independent, or manipulated variable, is a factor that’s intentionally varied by the experimenter. John is going to use 25g., 50g., 100g., 250g., 500g. of sugar in his experiment.

Dependent Variable The dependent, or responding variable, is the factor that may change as a result of changes made in the independent variable. In this case, it would be the size of the loaf of bread.

Formulate a Hypothesis Activity: Develop a Hypothesis Ex. If I put gas in my car, then it will start.

Experiment John comes up with a procedure and list of needed materials. John discusses with his teacher how to determine the control group.

Control Group In a scientific experiment, the control is the group that serves as the standard of comparison. The control group may be a “no treatment" or an “experimenter selected” group.

Control Group The control group is exposed to the same conditions as the experimental group, except for the variable being tested. All experiments should have a control group.

Control Group Because his grandmother always used 50g. of sugar in her recipe, John is going to use that amount in his control group.

Constants John remembers to keep all other factors the same so that any observed changes in the bread can be attributed to the variation in the amount of sugar.

Constants The constants in an experiment are all the factors that the experimenter attempts to keep the same. What would be some constants in this experiment?

Project Design Get someone’s opinion on your experimental design before you begin. Look at all the variables. Independent as well as dependent Open ended questions are a way of allowing for critical thinking to begin, but sometimes we start with the basics. Following directions are essential when doing a lab.

Experiment Activity: Develop a materials list and identify a control group. Ex. Materials: 5 gallon gas can, 5 gallons gasoline, money to buy gasoline, a ride to the gas station Control group: Not doing anything to the car.

Experiment Activity: Develop a procedure for your experiment. Procedure: First, I will call my friend Bill and ask for a ride to the gas station. I will take the five gallon gas can and fill it with five gallons of gasoline at the pump. After paying the gas station owner for the gasoline, I will get a ride back to my car and put the gasoline in the tank. Once the gasoline is in the tank, I will attempt to restart the car.

Collect and Analyze Results Activity: Make up realistic data. Ex. Action performed Did nothing Added gas Pumped the peddle ResultDidn’t start Almost started Started

Conclusions Activity: Draw your own conclusions Ex. My hypothesis was supported by the data. It shows that after adding gas the car started.

A graphic organizer is an instructional tool used to visually illustrate a topic.

describe a central idea

describe the stages of something –the life cycle of a primate –a sequence of events

time lines –showing historical events or ages –degrees of something

Compare/Contrast –How are they similar? –How are they different? Name 1Name 2 Attribute 1 Attribute 2 Attribute 3

Problem/Solution Outline –What was the problem? –What attempts were made to solve the problem? –Did those attempts succeed?

Network Tree –show causal information (causes of poverty), –a hierarchy (types of insects) –branching procedures (the circulatory system)

Cycle –weather phenomena –the life cycle –water cycle