The Building Blocks of Science

All scientific discoveries start with experiments! On the ACT, you'll read about how scientists design and carry out investigations.

Parts of an Experiment

• Hypothesis: What are they trying to prove?
• Variables: What do they change, and what do they measure?
• Control: What stays the same to make the test fair?

Using This Knowledge

Knowing how experiments work helps you judge the reliability of results—useful for both test questions and real-world decision-making, like evaluating product claims.

Look Out For

• Flaws in experiment design
• Logical conclusions based on the data