Scientific Literacy and Critical Thinking
What to master
Expect questions on the scientific method (observation, hypothesis, variables, controlled experiment, conclusion), independent vs. dependent variables, evidence vs. claim, and basic content: states of matter, energy transfer, ecosystems, the water cycle, human body systems, and heredity basics. Critical-thinking items ask you to spot correlation vs. causation, biased samples, unreliable sources, and faulty reasoning such as hasty generalization or appeal to emotion.
Common traps
- A study shows two things happen together; the question tests whether you wrongly conclude one causes the other.
- "Control group" vs. "experimental group" swapped in the choices.
- A conclusion that goes beyond the data (e.g., testing one plant species and concluding about all plants).
- Confusing a hypothesis (testable prediction) with a theory (well-supported explanation).
Rule of thumb
Ask three questions of any claim: What is the evidence? Is the sample fair? Does the conclusion match the data? If a choice uses words like always, never, proves, be suspicious unless the data are that strong.
Worked example
A student waters Plant A with plain water and Plant B with sugar water, placing A near a window and B in a closet. After two weeks, A is taller. What is the flaw? Two variables changed at once (water type and light), so height cannot be attributed to sugar water. The fix: keep light, soil, and pot size constant and change only the water. This is the controlled experiment principle.