Benchmark 1A
The Nature of Science: The Scientific World View
Grades 9-12, page 8

No matter how well one theory fits observations, a new theory might fit them just as well or better, or might fit a wider range of observations. In science, the testing, revising, and occasional discarding of theories, new and old, never ends. This ongoing process leads to an increasingly better understanding of how things work in the world but not to absolute truth. Evidence for the value of this approach is given by the improving ability of scientists to offer reliable explanations and make accurate predictions.

NSES Content Standard G  
History and Nature of Science: Science as a human endeavor 
Grades K-4, page 141 
Although men and women using scientific inquiry have learned much about the objects, events, and phenomena in nature, much more remains to be understood. Science will never be finished. 

NSES Content Standard A  
Science as Inquiry: Understanding about scientific inquiry 
Grades 5-8, page 148 
Scientific explanations emphasize evidence, have logically consistent arguments, and use scientific principles, models, and theories. The scientific community accepts and uses such explanations until displaced by better scientific ones. When such displacement occurs, science advances. 

NSES Content Standard A 
Science as Inquiry: Abilities necessary to do scientific inquiry 
Grades 9-12, page 175 
Recognize and analyze alternative explanations and models. This aspect of the standard emphasizes the critical abilities of analyzing an argument by reviewing current scientific understanding, weighing the evidence, and examining the logic so as to decide which explanations and models are best. In other words, although there may be several plausible explanations, they do not all have equal weight. Students should be able to use scientific criteria to find the preferred explanations.