NSES Content Standard A 
Science as Inquiry: Abilities necessary to do scientific inquiry
Grades 9-12, page 175

Identify questions and concepts that guide scientific investigations. Students should formulate a testable hypothesis and demonstrate the logical connections between the scientific concepts guiding a hypothesis and the design of an experiment. They should demonstrate appropriate procedures, a knowledge base, and conceptual understanding of scientific investigations.

Benchmark 1B The Nature of Science: Scientific Inquiry
Grades 9-12, page 13
Hypotheses are widely used in science for choosing what data to pay attention to and what additional data to seek, and for guiding the interpretation of the data (both new and previously available).