The Scientific Method Problem Solving for Science Detectives

What is the scientific method...

The scientific method is... … a problem solving tool used by scientist to determine the validity of a hypothesis. … an organized process for finding a solution to a question.

Scientific Method Steps Step #1: State the problem in the form of a question or statement. Begin with a solid problem or question. “What affect will temperature change have on the break-down of starch?”

A good question can be … l Examined l Analyzed l Measured

Choose a problem… l …that you do not know the answer to. l …a problem that you can work with.

Remember in Stating the Problem You are …. l Attempting to explain something that occurs repeatedly l Trying to solve something that is not working l Trying to create something to make life better

Step #2 : Research the problem l Research is a critical part of any science project or experiment. l Use a wide variety of resources l Make good observations while researching.

l Scientist rely heavily on the scientific method because there are so many variables to consider and any one of them can affect the results of the experiment. Research can either make or break the project or experiment.

l Gather information that might be useful in answering problem l Determine what information and tests are still needed Research can either make or break the project or experiment-continued.

From identifying and researching the problem move to step #3: … …form a hypothesis. A hypothesis must be… … an educated guess about a possible solution or answer to your problem or question. … testable. … precise. … measurable. That educated guess comes from the research you did

Step #3 Continued Developing a good hypothesis is the most difficult step of the scientific method Your hypothesis is the center of the project.

It is written in the form of an ‘if…, then..’ statement. If the hypothesis doesn’t make sense, then the whole project won’t make sense. Stick with a simple statement. Remember to make it testable, precise and measurable. Step #3 Continued

Step # 4: Write down the procedures that will be used to test your experiment lDlDesign an experiment to test the hypothesis. lAlA Grocery List of supplies lSlStep by Step procedure

Detail the entire experiment Writing your procedures will: a)Help one gather the necessary materials for the experiment. b)Make sure that the experiment fits the hypothesis being tested. c)Help others who want to repeat the experiment.

Step#5: Perform the experiment to test the hypothesis l #1 rule for testing a hypothesis is to always follow the written procedures. l Note any changes to the materials or methods used

Control is the key! Experiments are divided into two groups: The Experimental & The Control Group Group

Control vs. Experimental l Control group: l No variables are being tested. l The variables are constant meaning they do not change throughout the experiment. l Gives us a control for comparison with the experimental group. l Experimental group: l All parts are the same as the control group except one... l … the experimental variable (factor). l This is the variable being tested. l Independent Variable

By recording all the variables analyzed, scientists are able to track the validity of the hypothesis. Establish a baseline measurement: something to measure our variables with.

Identify the groups! Experimental Group Control Group Experimental Variable

Step # 6: Observe and record all results l While performing an experiment: 1. Always observe and record data accurately and objectively. You observe things as they are. Not the way you would like for them to be. This being ethical. You never falsify results. This is referred to as bias.

Use ‘tools’ to record and organize experimental results.

l 2. Watch your experiment closely and note any reactions that occur. Step # 6: Observe and record all results

Step # 7: Interpret the data l When interpreting the data be sure to : 1. Make tables, charts and graphs. 2. Draw pictures or take photographs to show the procedures and results. 3. Write a summary. Interpret: to explain or give meaning to.

lMlModel – a representation of an idea, event, or object to help people understand it better Visualizing with Models

4. Collecting and Measuring Data a. Qualitative Data: characteristics, physical traits EXAMPLE: Red flower, green leaf, black soil b. Quantitative Data: numbers, quantities EXAMPLE: 23 students, 4.2 cm long; height Steps to the Scientific Method

Qualitative l Red l Far from the earth l Microscopic l Burns quickly l HotQuantitative l 700 nm wavelength l 300 million light years l Smaller than 1 meter l Burns candle at 1 cm per minute l 350 degrees Celsius

5. Interpreting Data (Constructing Graphs) a. Types of Graphs: 1. Line Graph – shows a relationship between IV and DV Steps to the Scientific Method

5. Interpreting Data (Constructing Graphs) a. Types of Graphs: 2. Bar Graph – shows a comparison between IV and DV

Steps to the Scientific Method 5. Interpreting Data (Constructing Graphs) a. Types of Graphs: 3. Pie Graph – shows percentages; must add up to 100%

5. Interpreting Data (Constructing Graphs) b. Graphs must have: Title Key Labeled Axes X Axis  IV Y Axis  DV Steps to the Scientific Method

This collected data has been written in a table

Tabled results are plotted on a graph. Temperature (Celsius) Grams of starch broken down per minute Temperature vs. Starch Breakdown

Identifying Variables l Independent variable – the variable you change is plotted on the horizontal or x-axis. l Dependent variable- the variable that is being studied to see how the independent variable affects it. This is plotted on the vertical or y-axis.

Points to remember: data must be measurable measured information is stated with SI standard of measure Proper units of measure are used.

Analyze the data… l …from the experiment l Look for repeating patterns of results

Step #8: Form a conclusion based on the data. l The purpose of the conclusion is to communicate the results to others. In the conclusion make sure the following questions are answered: 1.What happened? 2.Was it what one expected? 3.Did the results agree with the hypothesis? 4.Did it answer the original question?

l If the conclusion supports the hypothesis then repeat the experiment to make sure the results are always the same (consistent). This is confirmation. l If the results do not support the hypothesis, then modify the hypothesis. This is revision. l OR- Totally reject the hypothesis and start over. Form a conclusion based on the data- cont.

The conclusion includes... …having results that can be accepted by others. The experiment can be repeated by others and the same results will be observed. Trial 1 Trial 2

Scientific Theory l an explanation of things or events based on knowledge gained from many observations and investigations l It can be revised

Communicate results l To groups in person l By publications l By news media

Scientific Law l It is the summary (total) of many experimental results. l Laws tell only what happens, not why it happens. l A statement about what happens in nature that seems to be true all the time Law of Gravitation

Technology l Technology – the application of science to help people

Remember … 1. Start with a question 2. Determine a possible solution 3. Test your question 4. Draw conclusions based on your findings 5. Let others know your findings