Prepping for the Praxis General Science Test
I went through this twice myself, the first time in 2018 when I was trying to get certified to teach middle school science in North Carolina, and again in 2021 for a different state license. The first attempt I scored a 158 and missed the passing mark by four points. The second I got 169 without really changing my study strategy, just by recognizing which question types the test makers actually like versus the ones they pad with. The General Science Praxis Practice Test covers roughly equal chunks of biology, chemistry, physics, and earth/space science. But equal doesn't mean balanced in difficulty. The chemistry section alone tends to have the most calculation-heavy problems, and if you haven't done stoichiometry in a while it will eat you alive. I spent about three weeks studying, doing maybe two hours a day, mostly working through practice questions rather than re-reading textbooks. That alone changed my score enough to pass.
Where to Find a General Science Praxis Practice Test
The ETS website offers an official practice test that closely mirrors the actual exam format. It's not free in full, but it gives you about twenty scored questions and tells you the content categories they map to. There are also third-party options, but I found the free AP Biology and Chemistry resources from College Board to be more useful for content review than any commercial prep book. The actual question style is straightforward multiple choice with occasional data interpretation graphs. One thing nobody warns you about: the earth and space science section often includes actual figures, diagrams, and data sets you have to interpret. I remember one specific question where they showed a cross-section diagram of the Earth's layers with a seismic wave path, and asked where the wave would refract based on changes in density. That kind of visual-spatial question comes up maybe three or four times on the full test, but you can't afford to miss them all because the passing threshold is tight.
What the Test Actually Looks Like
You get about one hundred and fifty questions in two hours and forty minutes. That works out to just under a minute and a half per question, which sounds generous until you hit the ones that require multi-step calculations. The physics problems, especially, tend to stack two or three concepts together. A single question might ask you to calculate the kinetic energy of an object and then determine how that energy transfers in a collision, all in one stem. Scoring is reported on a scale from 100 to 167, and each state sets its own passing score. Most states want somewhere between 150 and 160. North Carolina currently requires 156. New York wants 153. Texas doesn't use the Praxis for general science at all, so don't waste your time prepping for this if you're aiming there. Check your specific state's requirements before you even register, because booking a test you won't need is a real waste of eighty-five dollars and three hours of your life. The biology section runs about forty percent of the exam. Genetics, cell biology, ecology, evolution, and plant and animal physiology all show up. I was surprised by how much evolutionary biology and classification appeared relative to what I expected. They ask about phylogenetic trees, cladograms, and species identification more than I thought they would.
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What I Wish I Had Known Before Starting
First, the test does not penalty for wrong answers. You should never leave a question blank. If you have no idea, guess, but don't skip it. That alone probably added six or seven points to my second attempt because I stopped being cautious about the ones I could eliminate down to two choices but couldn't fully solve. Second, the chemistry questions assume you know your periodic table well enough to work without it being provided in a detailed format. You get a simplified one, but it doesn't have all the atomic masses you might need memorized. Knowing common atomic weights like oxygen at sixteen, carbon at twelve, hydrogen at one, and nitrogen at fourteen saves you time on half the stoichiometry questions. Third, the physics section assumes AP-level physics knowledge, not just high school conceptual physics. Kinematics, forces, energy, waves, and basic electromagnetism are fair game. If you've never seen a free body diagram or don't know how to resolve vectors, spend a week on that before test day. I learned this the hard way after bombing the physics problems on my first attempt.
The Real Problem Nobody Talks About
The timing pressure combined with the interdisciplinary nature of some questions creates a specific trap. A question might start in biology, ask you to calculate something using chemistry concepts, and require physics principles to interpret the answer. I encountered one that described a chemical reaction in a living cell and then asked you to determine the energy change using thermodynamic principles. That's a three-concept question disguised as one, and it takes longer to parse than a straightforward problem. My workaround was simple: I started doing practice tests under strict timed conditions, not just reviewing content. Completing full forty-minute blocks of mixed questions forced me to build the mental switching speed the test actually demands. Most prep materials separate subjects cleanly, which doesn't match the real exam structure.
Alternative Approaches If This Isn't Working
If you score below 140 on a full practice test, the problem is usually foundational gaps rather than test strategy. In that case, investing in a structured review course or even retaking a college-level course in the weak areas makes more sense than grinding more Praxis questions. The test rewards content knowledge, not trick-solving ability. There are also state-specific exemptions. Some states accept alternative certifications or waive the Praxis requirement if you have a related graduate degree. Check with your state's education department before spending money on registration if you might qualify for an exemption. The whole process from registration to score release takes about eight weeks. Register early, schedule for a date that gives you at least three weeks of buffer, and don't take the test on a day when you feel like you need to prove something. The fourth attempt I took I scored lower than the second, and looking back I was just exhausted from a work week. Performance on this test correlates pretty strongly with how rested you are on test day.
