Theory
A well-supported explanation about the natural world.
Model
A visual, mathematical, or three-dimensional representation of something in the natural world, often smaller than the original.
Law
Describes a basic principle of nature that always occurs under certain conditions.
Experiment
An organized procedure to study something under controlled conditions.
Observation
The process of obtaining information by using one or more of the five senses.
Hypothesis
A possible explanation for a set of observations or answer to a scientific question; must be testable.
Variable
Any factor that can change in an experiment, observation, or model.
Data
Information gathered by observation or experimentation that can be used to calculate or reason.
Inference
A logical conclusion based on observations.
Qualitative
Descriptive data using qualities, not numbers.
Quantitative
Data that is based on numbers.
Prediction
A statement made about the future based on evidence.
Evaluation
Reaching a conclusion based on observations.
Classification
The process of grouping items that are alike.
Investigation
Making an in-depth study of a subject.