S CIENTIFIC M ETHOD

S TEPS OF THE S CIENTIFIC M ETHOD 1. Observation 2. Hypothesis 3. Experiment 4. Data 5. Conclusion 6. Re-test

O BSERVATIONS Gathered information through your senses (what you see, hear, smell, etc.) Example: The neighbor who uses fertilizer in their garden has taller plants.

H YPOTHESIS A suggested solution to the problem Must be testable Must be an If…Then …statement NOT a question Example: IF plants are given fertilizer, THEN they will grow taller than plants without fertilizer.

E XPERIMENT A procedure to test the hypothesis. Involves only ONE variable that changes.

E XPERIMENT Variables - Independen t: the variable you are testing Example: fertilizer - Dependent : the variable that is being observed or measured (the data you collect) Example: plant height - Controls : the variables that stay the same Example: same type of plant, type of soil, type of planter, amount of water, amount of sunlight, etc. * The independent variable is the cause and the dependent variable is the effect.

E XPERIMENT Groups - Control : the group that does not have the variable being tested Example: the group not given the fertilizer - Experimental : groups that have different levels of the variable being tested Example: the group given the fertilizer Virtual Lab

D ATA Results of the experiment May be quantitative (numbers) or qualitative (observations based on senses) Can be organized into data tables, graphs, or charts Example: measure the height of the plants

C ONCLUSION The answer to the problem based on the data from the experiment Example: If the plants in the experimental group grow taller than the control group, the hypothesis is supported.

R E - TEST The experiment must be repeated to verify results.

C HARACTERISTICS OF A G OOD E XPERIMENT The sample size (number of subjects) must be large. Results are repeatable. Tests only one variable.