Scientific Method The process of scientific investigations What

Scientific Method The process of scientific investigations

What is the Scientific Method? The scientific method is a process used to find answers to questions about the world. These are the steps: 1. Ask a question (Question) 2. Gather information 3. State a hypothesis (Hypothesis) 4. Design an experiment (Experiment) 5. Make observations, record analyze data (Analyze data) 6. State and share conclusion (Conclusion)

Step 1: Question • What do you want to know or explain? • Use observations you have made to write a question that addresses that topic. • We will write our questions like this: independent variable How does _________ effect __________? Example: How does the amount of light effect a plant’s growth?

Variables The variable YOU can manage or change is the independent variable. It is independent because I change it. Example: Amount of light the plant gets (light all day, light 4 hours, no light) The variable that is the observed result of the changed independent variable is the dependent variable. It depends on the independent variable. Example: Plant growth (cm) Controlled variables are variables that do not change. Examples: ____________________________

Step 1: Question What is the effect of the type of shampoo on the smoothness of my hair? Independent variable (IV) Dependent variable (DV) • • You can change the type of shampoo you use when washing your hair You cannot change the smoothness of your hair without doing something to it… like changing your shampoo.

Step 2: Gather information • Researching your question lets you know if others have done this same experiment before and if so, what their data suggests. • You should also research scientific concepts related to the experiment. • Examples: Plant growth, plant development, sunlight, photosynthesis.

Step 3: Hypothesis • What do you think will happen? • A hypothesis is your prediction for the outcome of the experiment. • It is based on your observations and should be testable • Your hypothesis should be written in the following format: If…… then. …. because… Example: If I come to class everyday then I will earn a better grade because I am present to learn the material for the test.

Step 4: Experiment • Design a procedure that tests your hypothesis. • Be sure to keep the environment constant to be BE sure your experiment tests your hypothesis. Ex: If you are testing your shampoo to see if it makes your hair smoother example constants: Conditioner water temperature amount of shampoo Number of washes style of washing type of brush …………. • An experiment will have many constants • Record all of your data and observations and put them into a table.

Step 5: Analyze Data An observation is the gathering of information by using our five senses: § Sight § Smell § Hearing § Taste § Touch There are two types of observations § Qualitative § Quantitative

Qualitative Observations § Qualitative observations describe what we observe. § “Qualitative” = quality (descriptive) § These observations use adjectives to describe something. Example: The flower has white petals. Example: Ms. Beardsley has blue eyes.

Quantitative Observations § Quantitative observations measure what we observe. § “Quantitative” = quantity (numerical) § These observations use numbers to measure something in a quantitative way. Example: The flower has seven petals. Example: Ms. Beardsley has two eyes.

Inferences § Inferences are an explanation for an observation you have made. § They are based on your past experiences and prior knowledge. § Inferences are often changed when new observations are made. § Again, observations are information we gather directly through our five senses…. inferences help explain those observations!

Here are some examples! § Observation: The grass on the school’s front lawn is wet. § Possible inferences: § It rained. § The sprinkler was on. § There is dew on the grass from the morning. § A dog urinated on the grass!

Last one! § Observation: A student is sitting in the main office. § Possible inferences: ? Why might a student be sitting there?

Step 6: Analyze Data • Is your data reliable? • Put your data into a chart or graph and look for any trends.

Step 7: Conclusions • Do your data and observations support your hypothesis? • If you cannot make a definite conclusion, you may need to try again. • This means you may either need to rewrite your procedure if it was not specific enough; you may need to change your hypothesis.

Step 7: Conclusions • Report the results of your experiment to let others know what you learned. • This will be represented as either a lab report, oral presentation, or Science Fair display board. • Scientists may want to repeat your procedure to see if they get the same results as you. They may also tweak your experiment a little and have a slightly different focus. • Also, your report may lead to a new question which may lead to another investigation. This of course brings us right back to the first step again!