Benchmark 1B
The Nature of Science: Scientific Inquiry
Grades 6-8, page 12

Scientists differ greatly in what phenomena they study and how they go about their work. Although there is no fixed set of steps that all scientists follow, scientific investigations usually involve the collection of relevant evidence, the use of logical reasoning, and the application of imagination in devising hypotheses and explanations to make sense of the collected evidence.
 

NSES Content Standard A 
Science as Inquiry: Abilities necessary to do scientific inquiry 
Grades 5-8, page 145 
Develop descriptions, explanations, predictions, and models using evidence. Students should base their explanation on what they observed, and as they develop cognitive skills, they should be able to differentiate explanation from description--providing causes for effects and establishing relationships based on evidence and logical argument. This standard requires a subject matter knowledge base so the students can effectively conduct investigations, because developing explanations establishes connections between the content of science and the contexts within which students develop new knowledge. 

NSES Content Standard A 
Science as Inquiry: Understanding about scientific inquiry 
Grades 5-8, page 148 
Current scientific knowledge and understanding guide scientific investigations. Different scientific domains employ different methods, core theories, and standards to advance scientific knowledge and understanding. 

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.