ACT Science: Strategy & Drills

By Brian Stewart, Barron’s Author & ACT Perfect Scorer

The ACT Science section trips up more students than almost any other part of the test, and the cause is almost always the same: most students misunderstand what they’re actually being asked to do. After 20+ years of tutoring, I’ve found that the most important thing to understand about this section is that ACT Science is mostly a data-reading and reasoning test. Roughly 85% of questions can be answered entirely from the passage in front of you, with no outside knowledge. The other 15% draw on basic science concepts you may recognize from school, but these are never obscure: think understanding what a control group is, knowing that enzymes are proteins, or recognizing that higher frequency means shorter wavelength. The core skill this section tests is careful reading.

How the ACT Science Section Works

The ACT Science section is 40 questions in 40 minutes, organized into several passage sets. Each passage presents a scientific scenario (an experiment, a set of figures, or a debate between scientists) followed by five to seven questions. The passages fall into three types: Data Representation, Research Summaries, and Conflicting Viewpoints. Understanding how each type works is the foundation of a strong Science strategy.

Starting with the enhanced ACT (fully in effect for all test formats as of September 2025), Science is optional. Your composite is calculated from English, Math, and Reading only, and Science is reported as a separate score. Whether you should take it depends on your situation; see the FAQ below for guidance.

The Three Passage Types

Data Representation

Data Representation passages present one or more graphs, tables, or diagrams and ask you to read and interpret the data. Questions test your ability to read values directly from a figure, identify trends, interpolate between data points, and translate information between different representations. These are usually the most straightforward questions on the section because the answers are right there in the figures. The main pitfall is misreading axes: always check the axis labels, units, and scale before drawing any conclusion.

Research Summaries

Research Summaries passages describe one or more experiments and present their results. Questions go beyond simple data reading to ask about experimental design: the independent variable, what was held constant, what the results mean, and how changing conditions would change the outcome. These questions reward careful reading of the experimental setup as much as the results. Before you answer anything, make sure you know what each experiment was testing and how it was controlled.

Conflicting Viewpoints

The Conflicting Viewpoints passage presents two or more competing hypotheses about a scientific question, offered by scientists, students, or theoretical models. It’s mostly text-based and often has no graphs or tables at all, though occasionally a figure appears. Questions ask you to understand each viewpoint individually, identify where they agree and disagree, evaluate what evidence would support or undermine each position, and apply new information to determine which hypothesis it favors. Most students find this the toughest passage type because it’s closer to ACT Reading than to the other Science passages. Treat it that way: read each viewpoint carefully and separately before comparing them, and remember that the great majority of answers are supported by what the passage says. The occasional question may need a basic science concept, but the arguments and evidence are all in the text.

The Biggest Mistake I See on ACT Science

The most common error I see is students treating ACT Science like a science knowledge test and going blank when they hit unfamiliar terminology. When a passage discusses something they haven’t studied, they panic and start guessing instead of reading the passage for the information they need. The truth is that the ACT deliberately uses technical-sounding language to make passages feel intimidating, but the vast majority of questions are fully answerable from the passage alone. If a passage introduces a term you’ve never heard, it either defines it for you or the question only requires you to track how that term behaves in the data. A small number of questions, roughly 15%, do need a basic science concept from outside the passage, but these draw on foundational ideas (the role of a control, the relationship between wavelength and frequency, what enzymes do) rather than specialized knowledge. Trust the passage first, and go to outside knowledge only when the passage clearly doesn’t contain what you need.

How to Manage Your Time

With 40 minutes for 40 questions across several passages, you have about five to six minutes per passage. I recommend working through passages in the order they appear, with one exception: do the Conflicting Viewpoints passage last. It’s more text-heavy than the other passage types and needs a different mode of reading, and most students work through it more slowly. It’s easier to shift into that mode once the data-heavy passages are done. Within each passage, give it a brief look before jumping to the questions. For Data Representation and Research Summaries passages, scan the figures, graphs, and tables first to get your bearings on what each one is showing before you read a single question. For Conflicting Viewpoints, read the entire passage before answering anything, since you need to understand all of the viewpoints before the individual and comparison questions will make sense.

Four Things That Move Your ACT Science Score

1. Read Figures Before You Read Passage Text on Data Passages

For Data Representation passages, orient yourself to the figures first: read the title, axis labels, units, and any legend before you touch the questions. A lot of errors on this passage type come from misidentifying what a figure is actually showing. Thirty seconds of careful figure orientation will save you from misreading the data on every question that follows.

2. Understand the Design Before You Interpret the Results

For Research Summaries passages, the experimental design is at least as important as the results. Identify the independent variable (what was changed), the dependent variable (what was measured), and the controlled variables (what was held constant) in each experiment before you start answering questions. Questions about predicting results, modifying experiments, and identifying controls all require an understanding of the design that goes beyond reading numbers off a table.

3. Treat Conflicting Viewpoints Like a Reading Passage

When you reach the Conflicting Viewpoints passage, shift modes completely. It’s mostly text-based, so your job is to understand the competing arguments and compare them rather than read figures. For each viewpoint (whether from scientists, students, or models), identify the main claim, the evidence supporting it, and the points where it differs most from the others. Once you’ve worked through that for each viewpoint, the individual and comparison questions become much more manageable, and you’re much less likely to accidentally attribute one viewpoint’s position to another.

4. Trust the Passage Before Outside Knowledge

About 85% of ACT Science questions can be answered entirely from the passage. That means reaching for your general science knowledge before checking what the passage says is one of the most reliable ways to get questions wrong. The ACT sometimes presents data or scenarios where the “correct” answer according to the passage contradicts what you’d expect from a science class. When that happens, go back, find the support, and answer based on what the data and text actually show. For the roughly 15% of questions that do need outside knowledge, the concepts involved are foundational rather than specialized, and if you’ve been doing well in your science classes, you likely already know them.

How to Use These Drills

The drills below are organized by passage type. Each drill is an original passage and five questions, with a full explanation for every answer choice.

Work through each drill the way you would on test day: orient yourself to any figures, understand the experimental design or the scientists’ positions, then answer each question by going back to the passage for support. After you finish a drill, read every explanation, including for the questions you got right. Pay special attention to any question where you picked a wrong answer that felt convincing, and use the explanation to see exactly what made the correct answer better supported. The goal is to build the habits that produce the right answer consistently under time pressure.

For full ACT Science instruction with content review, complete practice tests, and detailed passage walkthroughs, check out Barron’s ACT Premium Study Guide.