ACT Science: To Take or Not to Take, and How to Practice: Not Included in the Composite Score, It Tests Graph Reading and Experiment Analysis

With the new ACT making the Science section optional—meaning you can get a composite score without taking it—many students' first question is, "Should I take it?" and the second is, "How do I prepare if I do?" The name "ACT Science" can be misleading, making students think they need to memorize a lot of physics, chemistry, and biology. However, the official ACT website makes it clear: it primarily tests scientific reasoning skills, not knowledge of any specific subject. For Chinese students with a strong STEM foundation and quick graph-reading skills, this section is often an opportunity to score high.

Based on the official ACT description of the Science section and the scoring guide for a new official online practice test, this article explains what Science tests, whether you should take it, and how to prepare. For the overall changes in the new ACT and how the composite score is calculated, see our guide on How to Score High on the ACT.

1. Should You Take the Science Section?

According to the new ACT test guidelines:

• For the ACT National Test (Saturday session), you can choose whether or not to take the Science section;
• The composite score is calculated only from English, Math, and Reading. Science is not included in the composite score, nor in the superscore;
• If you take Science, your score report will include a Science score, and Science and Math will be combined to produce a STEM score.

So, whether to take it mainly depends on two things (based on our experience):

1. Whether your target schools or majors have specific requirements or recommendations—always check the latest information on the school's official website;
2. Whether your Science score is comparable to your other scores. If you plan to apply to STEM majors and are good at Math, a high STEM score is a great asset; if Science significantly lowers your STEM score, you need to weigh your options.

The safest approach is to take an official Science practice test first to gauge your level, and then make a decision based on your target schools' requirements.

2. Basics of the Science Section

• 40 questions, 34 of which are scored, 40 minutes;
• Calculators are not allowed;
• Content covers Biology, Chemistry, Earth and Space Sciences (geology, astronomy, meteorology), and Physics;
• Official guidelines: No advanced subject knowledge is required, but background knowledge from introductory science courses may be needed.

3. Three Passage Formats

Research Summaries make up nearly half to 60% of the section, so understanding experimental design is the core skill for this section.

4. Three Skill Categories: Official Percentages and Practice Test Question Counts

The rightmost column comes from the scoring guide of a new official ACT online practice test (the third category is named "Evaluation of Models, Inferences, and Experimental Results" in the guide). As you can see, nearly half the questions involve reading graphs and tables.

5. Three Official Recommendations

1. Read the materials carefully: Read the text before answering, and clearly examine the tables, graphs, and diagrams related to the questions;
2. Pay attention to experimental design: Note the controls and variables, as these are frequently tested;
3. Distinguish between different viewpoints: Some passages present several conflicting viewpoints. You need to tell them apart. The official recommendation is to take notes and summarize each viewpoint.

6. How to Practice the Three Question Types

Here are some experience-based recommendations.

1. Interpretation of Data: Check the Axes and Units First

• When you get a graph, first check what the x-axis and y-axis represent and what the units are, then look at the trends;
• Many questions only require you to find a point on the graph or compare two curves. You don't need to read all the text first; you can go back to the graph to find the answer with the question in mind;
• For interpolation and extrapolation questions: estimate along the trend and look at the range of the options. Precise calculations are usually not needed;
• Calculators are not allowed, but calculations in Science questions are generally very simple, and estimation is usually enough.

2. Scientific Investigation: Identify the Independent Variable, Dependent Variable, and Controls

• For each experiment you read, write down three things: what was changed (independent variable), what was measured (dependent variable), and what was kept the same (control variables);
• When comparing multiple experiments, look at which condition was changed differently;
• For questions like "How should the experiment be modified to test a certain hypothesis?", the answer usually involves changing only one variable.

3. Conflicting Viewpoints: Summarize Each in One Sentence First

• Following the official recommendation, write a one-sentence summary of the core claim for each viewpoint as you read;
• Identify what the viewpoints agree on and where they differ;
• Questions often ask, "Which finding would support Viewpoint 1 and weaken Viewpoint 2?" Before answering, refer back to your summaries.

4. Brush Up on English Terminology

The questions are in English, so you need to be familiar with common terms: variable, control, hypothesis, trial, concentration, solution, temperature, pressure, density, velocity, mass, frequency, wavelength, etc. Just compile a bilingual glossary organized by subject.

7. A Practice Schedule (Example)

1. Week 1: Take a new official Science practice test, categorize your mistakes by the three skill categories, and decide whether to take the Science section;
2. Week 2: Focus on Interpretation of Data—practice reading graphs, identifying trends, and interpolating/extrapolating;
3. Week 3: Focus on Research Summaries and Conflicting Viewpoints—write down the variables and summarize the viewpoints for each passage;
4. Week 4 onwards: Do full 40-minute timed practice tests. When reviewing, categorize your mistakes as "misread the graph," "didn't understand the experiment," or "didn't know the concept."

In the old ACT, Science was included in the composite score, and the question count and time were different. You can use old questions to practice reading graphs and analyzing experiments, but do not use them for timing or score estimation.

Final Thoughts

ACT Science is not about memorizing facts; it's about reading graphs, understanding experiments, and distinguishing viewpoints. First, check if your target schools require it and how well you can score, then decide whether to take it. If you decide to take it, practice the three question types separately, and scoring high is not difficult.

For other ACT subjects, see our guides on How to Prepare for ACT English, How to Prepare for ACT Math, and How to Prepare for ACT Reading. If you need ACT prep tutoring, feel free to chat with our counselors.

Verification Note: This article was verified against official ACT materials in September 2026: Science is optional, the composite and superscores only include English, Math, and Reading, and Science and Math are combined into a STEM score, according to the new ACT test guidelines (PDF for educators); 40 questions, 34 scored, 40 minutes, according to the ACT test structure page (the ACT Science tips page states 35 minutes, which is inconsistent with the structure page; this article follows the structure page, but please refer to the official guidelines for your specific test date); content areas, the three passage formats and skill category percentages, no calculators allowed, and background knowledge requirements are from the ACT Science section description page; the three official recommendations are from the ACT Science tips page; the number of questions for the three skill categories in a test is from the scoring guide of the new official ACT online practice test. The advice on whether to take the test, how to practice each question type, the terminology list, and the practice schedule are our experience-based recommendations.

References:

• ACT：Description of the Science Test
• ACT：Exam Sections and Structure
• ACT：Science Test Tips
• ACT：The Enhanced ACT Test（PDF）
• ACT：Online Practice Test Scoring Key and Conversion Tables（PDF）