On ACT Science, you’ll have to think like a scientist, analyzing experiments and predicting outcomes.
If that sounds daunting, don’t worry. We’ve been helping students reach their goal ACT scores for over 20 years, and we’ve put together a step-by-step method for Research Summaries passages on ACT Science.
Plus, we’ve pulled together the latest data on the 25th, 50th, and 75th percentile ACT scores at hundreds of schools in our ACT Score Ranges resource. It’s free and you can grab it below!
Research Summaries passages on ACT Science are all about science experiments. Here’s what that looks like:
The passage will have a short intro, a few sentences long.
Then, you’ll see one or more sections labeled Experiment or Study. (If there’s more than one, they’ll be numbered.)
Each experiment will have one or more figures that go with it, typically showing results of the experiment. Sometimes, they’ll show information about the experimental setup instead.
Here’s an example of a typical Research Summaries passage:
Figure 1 sample ACT Science Research Summaries passage created by PrepMaven, all rights reserved
Research Summaries is one of 3 passage types you’ll see on the ACT Science section. You can read about the other two (Data Representation and Conflicting Viewpoints) here.
You’ll see 2-3 passages of this type on the entire ACT Science section, which has 7 passages total. The passages can come in any order.
There’s a lot to keep in mind, which is why we’ve put together a guide to everything you need to know about ACT Science – as well as essential strategies to improve your ACT Science score.
Now let’s go through the 3-step method for breaking down this passage type.
The 3-Step Method for Research Summaries Passages
When you see a Research Summaries passage on ACT Science, don’t get bogged down by trying to understand everything about the experiments. Instead, use this 3-step method to save time and pinpoint the answers you need:
Step 1: Skim the passage, but lead with the questions
Step 2: Make a cause → effect sketch for more complex questions
Step 3: Use key words to skim the passage for more detail (only when you have to!)
We’ll break down how to apply this method to ACT Science passages in just a minute. First, let’s take a quick look at the question types you’ll need to use it for.
Question Types on Research Summaries Passages
Each Research Summaries passage comes with a set of 5-6 questions.
Those questions fall into one of these categories:
Simply reading the data from figures. That’s it!
Understanding why a step was taken in the experiment.
Predicting how the results would change if you changed something in the experiment.
These are the questions you’ll see on Research Summaries passages. For all the question types on the whole ACT Science section, check out our list with examples over here.
When you’re ready to practice, here are 9 of the hardest ACT Science questions out there, along with detailed explanations for each one.
Now, let’s take a closer look at the step-by-step method to answer all these question types.
Strategy Tip #1: Skim the passage, but lead with the questions
When you’re looking at a Research Summaries passage, skim the passage – but don’t read it in detail yet.
Reading the whole passage in depth costs you valuable time. And most of the questions can be answered without looking at the passage at all.
Some students might even want to skip straight to the questions, which is fine.If you’re not comfortable with that, skim the passage and circle or underline key words or phrases as you read. Then go to the questions.
As you skim the questions, start with the ones that just ask for data from figures, like this example.
Based on the results of Study 1, approximately what percent of the seedlings that were grown in soil with a pH of 5.0 survived to 10 weeks?
F. 2% G. 4% H. 98% J. 96%
Instead of scouring the passage, head straight to the figure that shows the study’s results:
Table 2
Group
Soil pH
Seedling mortality (%)
1
4.5
12
2
5.0
4
3
5.5
2
4
6.0
8
Now locate the information you’re looking for: you’re interested in the group with a soil pH of 5.0. That group had mortality of 4%, meaning that the other 96% of seedlings survived. That’s answer choice J.
Notice that you didn’t need to know anything about the study to answer this question correctly. All you have to do is figure out what information you’re looking for, then figure out where to look for it.
If you’re aiming for a highly competitive – or even perfect – ACT score, mastering this skill will be essential. That’s where a specialist ACT tutor can make a big difference, helping you to learn and practice the key strategies you’ll need.
Strategy Tip #2: Make a cause → effect sketch for more complex questions
Two of the question types about Research Summaries that you’ll see are essentially about cause and effect:
Understanding why a step was taken in the experiment.
Predicting how the results would change if you changed something in the experiment.
These questions require a little more thinking, but you can usually still answer them without looking at the passage.
The key to these questions is to sketch the cause-and-effect relationship in just a few words. Then use that as a tool to answer the question.
In seawater, compound X is broken down into simpler compounds by thermal energy at temperatures above 50 degrees Fahrenheit. What action was taken in the studies to prevent this process from taking place?
A. Each mixture of compound X and seawater was cooled. B. Each mixture of compound X and lake water was cooled. C. Each mixture of compound X and seawater was exposed to light. D. Each mixture of compound X and lake water was exposed to light.
When you see a question like this, it’s tempting to look at the studies to see what the scientists did. But you don’t need to!
There’s a simple causal relationship here:
Seawater + higher temperature → compound X gets broken down
In this case, we’re told that this process was prevented, so we can assume that the scientists took away one of the causal factors on the “cause” side of this relationship.
We’re talking about seawater, not lake water, so you can cross off answers B and D straight away. Light exposure has nothing to do with the cause-effect relationship, so you can also eliminate answer C. That leaves answer A: to prevent the process from happening, the seawater mixture was cooled.
Here’s another example. This one is about predicting experimental results:
Based on the results of Experiment 1, if Experiment 2 were repeated except that all the piglets were fed Diet R instead of Diet Q, would the average body mass more likely have been lower or higher for each group?
F. Lower; on average, piglets fed Diet R had an average body mass 20 percentile points greater than those fed Diet Q. G. Lower; on average, piglets fed Diet R had an average body mass 10 percentile points smaller than those fed Diet Q. H. Higher; on average, piglets fed Diet R had an average body mass 10 percentile points greater than those fed Diet Q. J. Higher; on average, piglets fed Diet R had an average body mass 20 percentile points greater than those fed Diet Q.
Results of Experiment 1
Diet
Average body mass (percentile of control group body mass)
Q
45
R
65
S
75
T
55
This question is more complicated than just reading data. Still, you do not need to understand the experiment in detail.
You just need to identify how the experiment is changing and what effect that will likely have based on the data.
What’s changing? The piglets are getting fed a different diet.
What do we want to know? How this will affect their average body mass.
What do we already know? The average body mass for piglets on different diets.
Based on the data, we can see a cause-effect relationship. Diet R leads to a body mass in the 65th percentile. That’s higher than the old diet, diet Q. Here’s the cause-effect relationship:
Piglets eat diet R → piglets get heavier; piglets eat diet Q → piglets get lighter.
So if we switch all the piglets to Diet R, we can expect average body mass to go up. That eliminates answers F and G.
Now, use the process of elimination to choose between answers H and J. The only difference is something you can easily verify in the tablt above: how much greater is the average body mass on Diet R than on Diet Q?
On Diet R, the average body mass was in the 65th percentile. On Diet Q, the average body mass was in the 45th percentile. So 65 – 45 = 20 percentile points difference. That’s answer choice J.
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Strategy Tip #3: Use key words to skim the passage for more detail (only when you have to!)
You might also see some questions that require a bit of information from the passage, like this one.
In the experiments, 2 g of food was added to each tank at each feeding. How many grams of food were placed into each tank each day?
A. 2 B. 4 C. 8 D. 12
Let’s say that the figures don’t give you any information about food. You have to look at the passage – but instead of wading through the whole text, identify key words and then skim the text for those. In this case, key words could be food and feeding.
Skim the passage with those words in mind:
Neocaridina davidi, a species of freshwater shrimp, are kept in many home aquariums. Two experiments were conducted to determine how diet and stocking density (number of shrimp per liter of water, shrimp/L) affect the specific growth rate (SGR; percent increase in length per day, percent/day) in N. davidi.
Experiment 1 Each of 12 identical 10 L tanks received 8 L of freshwater with a specific hardness of 8 dGH, a temperature of 22°C, and a pH of 7.5. Hardness, temperature, and pH were kept constant over the course of the experiment. N. davidi of similar lengths were selected, and their lengths were measured, in mm. They were then equally distributed among the tanks at a stocking density of 2 shrimp/L. The tanks were then divided equally into 4 groups.
For 3 months, each group was fed a different diet (Diets Q–T). Each group was fed twice a day. At the end of 3 months, the length of each shrimp was measured, in mm, and the SGR of each shrimp was calculated. The average SGR was then determined for each group (see Table 1).
Buried in a ton of irrelevant information, there’s our clue: “Each group was fed twice a day.” And if each feeding provided 2 grams of food, as the question said, then that totals 2 x 2 = 4 grams of food, or answer choice B. It’s first-grade-level math – you just have to find the information you need.
Circling or underlining key words as you skim the passage will help you save time, since you can quickly come back to the most important parts of the passage. That’s why annotating is one of the most helpful ACT strategies.
We’ve lined up 7 more key strategieshere that will help you on every type of ACT Science question.
Next Steps
That’s all you need to know about Research Summaries on ACT Science!
The best way to get comfortable with this passage type is to practice the strategies we’ve gone through above. Working with a PrepMaven ACT expert can help you do just this! With one-on-one ACT tutoring, you’ll be well on your way to strategically approaching ACT Science and improving your score. Learn more about our options here, and get in touch with our team for a free consultation.
Rosamond graduated summa cum laude from Princeton. During college, she worked as a peer tutor for Italian, French, Greek, and academic writing. Since graduation, she’s continued to tutor students of all ages in French, Italian, Latin, English, and math, some of them for several years. She’s currently a graduate student studying the relationship between religion and secular law, and she works as a freelance journalist and translator.
