Key Takeaways

  • Separate independent variables, dependent variables, constants, and controls quickly.
  • Read graphs for trends, slope, proportionality, and whether the data actually supports the claim.
  • Know the difference between observation, inference, hypothesis, theory, and law.
  • Engineering-design questions usually reward iterative testing under real-world constraints.
Last updated: March 2026

What This Domain Really Tests

Praxis General Science does not use the inquiry domain only to ask vocabulary questions. It tests whether you can:

  • identify variables and controls in an investigation
  • interpret graphs and data tables accurately
  • judge whether a conclusion is supported by evidence
  • choose safer or more valid procedures
  • apply the engineering design process to solve a problem under constraints

High-Yield Review Points

Focus on:

  • experimental design: independent variable, dependent variable, constants, control group
  • measurement and graphing: units, scale, trends, interpolation, precision vs accuracy
  • nature of science: models change with evidence; theories explain broad patterns; science is evidence-based and revisable
  • lab safety: goggles, wafting, heat and chemical handling, proper disposal, and safe equipment use
  • engineering design: define the problem, identify constraints, prototype, test, revise

Fast Elimination Rule

On inquiry questions, eliminate answers that:

  • claim more than the data supports
  • confuse correlation with causation
  • fail to control a key variable
  • use unsafe lab practice
  • treat science as fixed authority instead of evidence-based explanation
Test Your Knowledge

A student tests whether fertilizer affects plant height and keeps light, soil, pot size, and water the same. What is the independent variable?

A
B
C
D
Test Your Knowledge

Which statement best reflects the nature of science?

A
B
C
D