Science is the study of nature at all levels, from the infinite to the infinitesimal. It is the asking and answering of questions about natural processes or phenomena that are directly observed or indirectly inferred. From these questions and answers come tentative explanations called hypotheses, which lead to testable predictions about the natural processes and phenomena. Hypotheses that withstand rigorous testing of predictions will gradually lead to an accretion of facts and principles, which serve as the foundation of scientific theories.

The scientific method is a process for predicting, on the basis of a handful of scientific principles, what will happen next in a natural sequence of events. Because of its success, this invention of the human mind is used in many fields of study. The scientific method is a flexible, highly creative process built on three broad assumptions:

  • Change occurs in observable patterns that can be extended by logic to predict what will happen next.
  • Anyone can observe something and apply logic.
  • Scientific discoveries are replicable.
California Department of Education: Science Framework for California Public Schools 2004