The Scientific Method The series of steps used to gather information and solve a problem.

Science is… n An organized way of using evidence to learn about the natural world. n Goal: investigate and understand nature, to explain events in nature, & use events to make predictions.

Step 1: State the Problem Make Observations- sights, sounds, smells, tastes etc. that are actually perceived by a scientist Develop inferences -logical interpretations based on observations. State the problem that you want to solve in the form of a ____________________.

(answer on your paper) n Mrs. Howard lives near a park where boys often play baseball. One day, he heard a crash and the clinking of broken glass. Upon entering the living room, he found a broken window. As he opened the front door & looked out, he saw Johnny running past the house carrying a baseball bat. n Based on the above description: –List 3 Observations –List 3 Inferences

Step 2: Hypothesis A hypothesis is a testable explanation to your question. It includes your prediction- the expected outcome of your experiment if your explanation is correct. Write your hypothesis as an If, then statement. Example: If the food contains salt, then it will glow.

Step 3: Design and Perform the Experiment Test only one variable (The Experimental group) Independent variable (Manipulated) – factor that the scientist changes during the experiment. Dependent variable (Responding)– the factor that changes as a result of the scientist’s actions. The hypothesis should identify your variables: If (Independent), then (Dependent) Include a control group which receives no experimental treatment, and can be used for comparison with the experimental group.

Step 4: Analyze Data Use graphs/charts/tables to display your data Data can be qualitative (descriptive) or quantitative (numerical) Use DRY MIX to remember how to graph your data (next slide) Identify any trends or patterns in the data Explain any error that may exist in your data

Variables continued… n When Graphing: –Dependent variable –Responding –Y axis (DRY) -Manipulated -Independent variable -X axis (MIX)

Step 5: Write your Conclusion State whether your hypothesis was supported or rejected hypothesis – refer back to your original hypothesis. Cite specific data evidence from your experiment to explain why. Identify possible error in your experiment. Consider related areas for further study.