| Term | Definition |
| Independent Variable | The one and only thing changed in an experiment. |
| Dependent Variable | Changes in response to the independent variable. The measurable factor in an experiment that answers the original comparative question. |
| Controlled Variables | The things that are kept the same in an experiment. |
| Uncontrolled Variable | The things that are accidently not kept the same in an experiment. |
| Observation | The process of collecting information from your five senses that everyone can agree upon. |
| Inference | A possible explanation or guess that is based on an observation. There may be many differing opinions. |
| Qualitative Observations | Observations that describe qualities of an object such as color or shape. |
| Quantitative Observations | Observations that include numbers (quantities), such as size. |
| How does the amount of vitamin C compare in different fruit drinks? ID the variables | IV-Brand of juice DV- Amount of Vitamin C Controlled: Amount of juice tested |
| Does the type of antibacterial agent you use to clean a washing machine affect the number of bacteria found in it? ID the variables | IV-Antibacterial agent DV-Number of bacteria Controlled-same amount of cleaning agent used |
| Is there more lead in soil located closer or further away from a roadway? ID the variables | IV-Distance from road DV-Lead in soil Controlled-Same amount of soil |