D2.Psy.11.9-12: How Psychological Science Studies Differences in Cognitive and Physical Abilities
In plain English: D2.Psy.11.9-12 is the C3 Framework psychology indicator for grades 9-12 that asks students to identify the role psychological science can play in understanding differences in individual cognitive and physical abilities. Students learn how researchers measure abilities, describe how people vary, test which abilities go together and what changes them, and use the results responsibly.
Identify the role psychological science can play in helping us understand differences in individual cognitive and physical abilities.
C3 Framework for Social Studies (NCSS) · Dimension 2: Applying Disciplinary Concepts and Tools · Discipline: Psychology · Influences on Thought and Behavior · Official standard
D2.Psy.11.9-12 asks students to identify the role psychological science can play in helping us understand differences in individual cognitive and physical abilities. Cognitive abilities include attention, memory, reasoning and processing speed; physical abilities include strength, speed of movement, balance and the acuity of the senses. Psychological science plays at least five roles: it measures abilities with defined procedures, describes how much people vary, tests which abilities go together, studies what changes them (practice, age, health, environment), and sets rules for using the results fairly.
The lesson follows one early chapter of that story. In 1890 James McKeen Cattell proposed a battery of simple tests, from grip strength to memory for letters; in 1901 Clark Wissler checked whether the scores went together and whether they predicted college marks. Two current federal sources, on noise-induced hearing loss and on cognitive training, show the same roles today. Invented class data let students compute and interpret a z-score and a correlation. Students plan studies on paper only.
Learning Objectives
By the end of this lesson, students will be able to:
Identify five roles psychological science plays in understanding differences in cognitive and physical abilities
Classify a measure as mainly cognitive, mainly physical or a mix, and write an operational definition for it
Use a mean, a standard deviation, a z-score and a correlation to describe how individuals differ
Evaluate historical and current claims about abilities using evidence, and flag outdated ideas
Explain how differences within groups and the limits of a test should shape how results are used
Prior Knowledge Required
Students should already be comfortable with:
Validity and reliability of measurements D2.Psy.5.9-12
How nature and nurture interact D2.Psy.10.9-12
Mean and standard deviation of a data set HSS.ID.A.2
"Think of one thing you do better than most people your age and one thing you find harder than most. How would you prove either difference to a stranger, using numbers?"
Collect a few answers. Students usually discover that they need a task, a score, a comparison group and more than one try. Write those four needs on the board: they are the start of psychological measurement. Ask whether either difference might change with practice, age or equipment.
Direct Instruction20 minutes
Individual differences are the ways people differ from one another on a measured trait. An ability is a capacity to perform a kind of task; a cognitive ability involves mental work such as remembering or reasoning, and a physical ability involves the body, such as strength, speed of movement or the senses. Many real tasks mix the two.
Five roles of psychological science in understanding ability differences (summary written for this page)
Role
What it means
Tools
Measure
Define each ability as a task with a score, given the same way to everyone
Operational definitions, standardized procedures, reliability and validity checks
Describe
Show how scores are spread across people
Mean, standard deviation, z-scores, distributions
Relate
Find out which abilities go together
Correlation
Explain
Find out what makes abilities differ or change
Experiments, twin and long-term studies, training trials
Apply responsibly
Use results to support people, not to label them
Accommodations, prevention, design that fits people, rules against misuse
A z-score tells how far a score is from the mean in standard deviations: z = (score - mean) / SD. A correlation (r, from -1 to 1) tells how closely two measures go together across people; r near 0 means knowing one score tells you little about the other.
Read Source 1. James McKeen Cattell (1860-1944) had studied in Wilhelm Wundt's laboratory in Leipzig and in Francis Galton's circle in England, and in this 1890 article, titled "Mental Tests and Measurements," he proposed one standard series of tests for many people.
1Psychology cannot attain the certainty and exactness of the physical sciences, unless it rests on a foundation of experiment and measurement. A step in this direction could be made by applying a series of mental tests and measurements to a large number of individuals. The results would be of considerable scientific value in discovering the constancy of mental processes, their interdependence, and their variation under different circumstances. Individuals, besides, would find their tests interesting, and, perhaps, useful in regard to training, mode of life or indication of disease. The scientific and practical value of such tests would be much increased should a uniform system be adopted, so that determinations made at different times and places could be compared and combined. With a view to obtaining agreement among those interested, I venture to suggest the following series of tests and measurements, together with methods of making them.
2The first series of ten tests is made in the Psychological Laboratory, of the University of Pennsylvania on all who present themselves, and the complete series on students of Experimental Psychology. The results will be published when sufficient data have been collected. Meanwhile, I should be glad to have the tests, and the methods of making them, thoroughly discussed.
3The following ten tests are proposed:
4I. Dynamometer Pressure.
5II. Rate of Movement.
6III. Sensation-areas.
7IV. Pressure causing Pain.
8V. Least Noticeable difference in Weight.
9VI. Reaction-time for Sound.
10VII. Time for naming Colours.
11VIII. Bi-section of a 50 cm. Line
12IX. Judgment of 10 seconds time.
13X. Number of Letters remembered on once Hearing.
14It will be noticed that the series begins with determinations rather bodily than mental, and proceeds through psychophysical to more purely mental measurements.
James McKeen Cattell, Source 1: Cattell proposes ten tests for every person tested (1890) (1890). Public domain (published 1890). Source text.
Then read Source 3. Clark Wissler, a graduate student at Columbia, where Cattell then taught, used the test records of Columbia College and Barnard College students to check how well the scores went together. Sample warning: his data came from college students in New York around 1900, a narrow group by age, schooling and background, so his results describe that group.
1This research is occasioned by the fact that psychologists and students of education have proposed certain tests, put them to trial and recorded their results, hoping thereby to find a means by which the fundamental elements of general and specific ability could be isolated and valued. [...] The most obvious line of approach in this problem is through correlation. If a test is general, then its results should correlate with many other special tests, and, in turn, if there is an integral relation between general and special ability, the results of the latter should correlate with the former. Should two tests show no correlation whatever, we can do no more than regard them as defining two entirely independent forms of activity.
[...]
2The general conclusions are:
31. That the laboratory mental tests show little intercorrelation in the case of college students.
42. That the physical tests show a general tendency to correlate among themselves but only to a very slight degree with the mental tests.
53. That the markings of students in college classes correlate with themselves to a considerable degree but not with the tests made in the laboratory.
Clark Wissler, Source 3: Wissler tests the tests (1901) (1901). Public domain (published 1901). Source text.
Who was measured: Source 1, paragraph 2
Cattell's first series was given "on all who present themselves" at his laboratory. What does that tell us about the sample?
Result: It is a self-selected sample: the people who chose to come to a university laboratory. Their scores describe that group, not people in general, and anyone comparing a person with them should know who was in it.
A z-score on a new scale
On an invented balance test, a group's mean is 30 seconds standing on one foot, with a standard deviation of 8 seconds. Mia holds 42 seconds. What is her z-score?
Result: z = (42 - 30) / 8 = 12 / 8 = 1.5. Mia is 1.5 standard deviations above this group's mean. The z-score describes her place in this group only.
Reading a correlation
Suppose two invented measures in a large sample correlate at r = 0.05. What can you say?
Result: Almost nothing links them: knowing a person's score on one barely helps predict the other. They probably measure separate abilities, or one of the measures is unreliable. A correlation also never shows by itself that one ability causes another.
An environmental cause of a physical difference
Source 4, paragraph 1 (printed in Independent Practice) says loud sounds "can damage sensitive structures in the inner ear." How does this change the way we explain differences in hearing?
Result: Some differences in a physical ability come from exposure, not from birth. That makes them partly preventable, and it means a hearing score reflects a person's history as well as their biology.
Differences within and between groups
Two invented classes have mean reaction times of 220 ms and 226 ms, and each class has a standard deviation of 20 ms. Is a student from the second class probably slower than a student from the first?
Result: No. The 6 ms gap between the means is small next to the 20 ms spread inside each class, so the two classes overlap almost entirely. Many students in the second class are faster than many in the first. Group averages say little about any one person.
Close the segment with a historical warning. In the early 1900s some psychologists used test scores to rank whole groups of people. Carl Brigham's 1923 book A Study of American Intelligence claimed differences among immigrant groups and was cited in debates about restricting immigration; in 1930 Brigham publicly withdrew his conclusions in the journal Psychological Review. That history is part of why the fifth role in the table matters.
Guided Practice15 minutes
Read Source 6 together. It is invented data, written to show what a small class demonstration of three measures might produce.
1Invented data, written for this page. Twelve volunteers in one high school psychology class, numbered 1 to 12, took three short measures in a teacher-run demonstration. Taking part was voluntary, and results were recorded by number, not by name.
2Reaction time: each student pressed a key as soon as they heard a beep. The score is the fastest of three tries, in milliseconds (ms); a lower score is faster. Scores for students 1-12: 209, 244, 196, 234, 191, 239, 218, 211, 237, 195, 247, 219. Mean 220 ms; standard deviation 20 ms.
3Letter span: the largest number of spoken letters the student could repeat back in order. Scores for students 1-12: 7, 6, 8, 6, 7, 7, 7, 8, 7, 6, 6, 9. Mean 7 letters.
4Grip strength: the stronger of two squeezes on a hand dynamometer, in kilograms (kg). Scores for students 1-12: 31, 38, 27, 40, 29, 35, 40, 26, 33, 37, 30, 42. Mean 34 kg.
5Correlations in this class: reaction time with letter span, r = -0.36; grip strength with letter span, r = -0.14.
SVHS (invented scenario), Source 6: One class, three measures (invented data) (2026). Original passage written for this page.
Classify. Which of the three measures is mainly cognitive, which is mainly physical, and which mixes both? Students defend their answers with Cattell's own remark about bodily and mental energy in Source 2.
Describe. Student 12 has a reaction time of 219 ms: z = (219 - 220) / 20 = -0.05, almost exactly average. Students compute z-scores for two other students themselves.
Relate. Look at Diagram 2. Do students who react faster tend to repeat more letters? How strong is the pattern?
Sample warning. Twelve volunteers from one class, each measured once on one day, is far too small a sample to say how these abilities are related in teenagers generally. Treat every number here as practice, not as a finding.
Independent Practice15 minutes
Students read Sources 2, 4 and 5 on their own and use all six sources for the quiz and homework. Source 2 gives Cattell's instructions for two tests; Source 4 is a federal page on noise and hearing; Source 5 is a federal page on cognitive training in older adults.
1I. Dynamometer Pressure. The greatest possible squeeze of the hand may be thought by many to be a purely physiological quantity. It is, however, impossible to separate bodily from mental energy. The 'sense of effort' and the effects of volition on the body are among the questions most discussed in psychology and even in metaphysics. Interesting experiments may be made on the relation between volitional control or emotional excitement and dynamometer pressure. Other determinations of bodily power could be made (in the second series I have included the 'archer's pull' and pressure of the thumb and fore-finger), but the squeeze of the hand seems the most convenient. It may be readily made, cannot prove injurious, is dependent on mental conditions, and allows comparison of right-and left-handed power. The experimentee should be shown how to hold the dynamometer in order to obtain the maximum pressure. I allow two trials with each hand (the order being right, left, right, left), and record the maximum pressure of each hand.
[...]
2X. Number of Letters repeated on once Hearing. Memory and attention may be tested by determining how many letters can be repeated on hearing once. I name distinctly and at the rate of two per second six letters, and if the experimentee can repeat these after me I go on to seven, then eight, &c.; if the six are not correctly repeated after three trials (with different letters), I give five, four, &c. The maximum number of letters which can be grasped and remembered is thus determined. Consonants only should be used in order to avoid syllables.
James McKeen Cattell, Source 2: Cattell describes two of the tests (1890) (1890). Public domain (published 1890). Source text.
1Every day, we experience sound in our environment, such as the sounds from television and radio, household appliances, and traffic. Normally, these sounds are at safe levels that don’t damage our hearing. But sounds can be harmful when they are too loud, even for a brief time, or when they are both loud and long-lasting. These sounds can damage sensitive structures in the inner ear and cause noise-induced hearing loss (NIHL).
[...]
2Exposure to harmful noise can happen at any age. People of all ages, including children, teens, young adults, and older people, can develop NIHL. Based on a 2011-2012 CDC study involving hearing tests and interviews with participants, at least 10 million adults (6 percent) in the U.S. under age 70—and perhaps as many as 40 million adults (24 percent)—have features of their hearing test that suggest hearing loss in one or both ears from exposure to loud noise. Researchers have also estimated that as many as 17 percent of teens (ages 12 to 19) have features of their hearing test suggestive of NIHL in one or both ears (Pediatrics 2011), based on data from 2005-2006.
[...]
3Sound is measured in units called decibels. Sounds at or below 70 A-weighted decibels (dBA), even after long exposure, are unlikely to cause hearing loss. However, long or repeated exposure to sounds at or above 85 dBA can cause hearing loss. The louder the sound, the shorter the amount of time it takes for NIHL to happen.
National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Source 4: National Institute on Deafness and Other Communication Disorders, Noise-Induced Hearing Loss (2025). US government work (17 U.S.C. 105). Source text.
1Cognitive health — the ability to clearly think, learn, and remember — is an important component of performing everyday activities. Cognitive health is just one aspect of overall brain health.
[...]
2Being intellectually engaged may benefit the brain. People who engage in personally meaningful activities, such as volunteering or hobbies, say they feel happier and healthier. Learning new skills may improve your thinking ability, too. For example, one study found that older adults who learned quilting or digital photography had more memory improvement than those who only socialized or did less cognitively demanding activities. Some of the research on engagement in activities such as music, theater, dance, and creative writing has shown promise for improving quality of life and well-being in older adults, from better memory and self-esteem to reduced stress and increased social interaction.
3However, a recent, comprehensive report reviewing the design and findings of these and other studies did not find strong evidence that these types of activities have a lasting, beneficial effect on cognition. Additional research is needed, and in large numbers of diverse older adults, to be able to say definitively whether these activities may help reduce decline or maintain healthy cognition.
[...]
4Some types of cognitive training conducted in a research setting also seem to have benefits. For the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial, healthy adults 65 and older participated in 10 sessions of memory training, reasoning training, or processing-speed training. The sessions improved participants' mental skills in the area in which they were trained with evidence suggesting these benefits persisted for two years.
5Be wary of claims that playing certain computer and online games can improve your memory and other types of thinking as evidence to back up such claims is evolving. There is currently not enough evidence available to suggest that computer-based brain training applications offered commercially have the same impact on cognitive abilities as the ACTIVE study training. NIA and other organizations are supporting research to determine whether different types of cognitive training have lasting effects.
National Institute on Aging (NIA), National Institutes of Health, Source 5: National Institute on Aging, Cognitive Health and Older Adults (2020). US government work (17 U.S.C. 105). Source text.
Task: build a two-column chart with the headings Physical ability and Cognitive ability. Under each, write one difference between people that a source describes, the source and paragraph, and which of the five roles of psychological science the source shows.
Closure5-10 minutes
Exit ticket: "Name one role of psychological science from today and one way it could be misused. What rule would prevent the misuse?"
Teacher notes. (1) Sources 1-3 are historical. Cattell's hope that simple sensory and speed tests would reveal general mental ability is outdated; Wissler's results are one reason. Neither source is current guidance on testing. (2) Source 4 reports survey estimates of hearing-test features, and Source 5 discusses research on older adults; neither is a way to judge any student. Students never test or score classmates' hearing, memory or health. A student with a concern about their own hearing or memory should talk with a parent, school nurse or doctor. (3) Source 6 is invented, and any class demonstration should be voluntary, anonymous and approved under your school's rules. (4) Differences in ability are not differences in a person's worth; keep the language of the lesson to measured tasks, not labels for people.
Differentiation Strategies
For Struggling Students
Give the five-roles table with one example from the sources already filled in for each role
Provide a worked z-score template: score, minus mean, divided by SD, with boxes for each step
Pre-sort Cattell's ten tests into three colored groups before students explain the sort
For Advanced Students
Explain why a measure with low reliability would also show low correlations with other measures, and what that means for Wissler's conclusion 1
Compare Source 5's two kinds of evidence (one study and a comprehensive report) and explain which deserves more weight
Research, then summarize in a paragraph, how test designers check that a test works the same way for different groups
Assessment Guidance
What to Look For
Strong answers name a specific role (measuring, describing, relating, explaining, applying), connect it to a cognitive or a physical ability with evidence, compute z-scores with the right sign, and keep group results apart from claims about individuals. Watch for students who read a lower reaction time as worse, who treat a correlation as a cause, or who use an ability score as a label for a person.
02
Classroom Activities
3 Activities
1
Design a Test Battery on Paper
20 minGroups of 3
Each group designs, on paper only, a short battery of four measures for a school's psychology club: two cognitive abilities and two physical abilities. Every measure needs a task, a score and a rule for how many tries count. No one is tested.
Test Battery Planning Sheet
The ability, and whether it is mainly cognitive, mainly physical or a mix
The task, described so that any teacher could give it the same way
The score and its unit (seconds, letters, kilograms, correct answers)
How many tries, and which try counts (best, average)
One threat to reliability (would the score be similar tomorrow?)
One threat to validity (does the task really measure the ability named?)
Safety and privacy: who sees the scores, and how they are kept anonymous
Debrief Questions
Which of your measures mixes bodily and mental effort most?
Would your battery give an unfair picture of a student who is ill, tired or new to the language of the instructions?
Which of the five roles in the Direct Instruction table does your sheet cover, and which does it leave out?
2
Station Rotation: Predict, Then Check With Wissler
15 minGroups of 4
Four stations each hold one card naming a pair of Cattell's measures or a measure and college marks: (1) grip strength of the right hand and of the left hand; (2) reaction time and memory for letters; (3) reaction time and college class standing; (4) marks in one college course and marks in another. At each station, groups predict whether the two would correlate strongly, weakly or not at all, and write one reason. Then they read Source 3 and revise.
Prediction Card (one per station)
Pair on the card
Prediction: strong, weak or none
Reason
After reading Source 3: which conclusion speaks to this pair, if any?
Revised prediction and why
Teacher Note
Source 3 prints Wissler's general conclusions, not his individual coefficients, so groups argue from the conclusions. Station 1 has no direct conclusion; ask what conclusion 2 suggests.
3
Claim Check: Two Ads About Abilities
15 minPairs
Pairs read two invented ads and decide what evidence each would need. Ad A: "Ten minutes a day with our phone game makes your whole brain faster, guaranteed." Ad B: "Our foam earplugs cut the sound of a concert so it is less likely to harm your hearing." For each ad, pairs write the claim, the ability it is about, whether it is cognitive or physical, and the kind of study that could test it.
Claim Check Sheet
The exact claim
The ability, and whether it is cognitive or physical
What a fair test would compare
What a source in this lesson says that is relevant, with its paragraph number
Your verdict: supported, partly supported or unsupported by what we have read
Variation
Have pairs rewrite each ad so that it claims only what the evidence in the lesson's sources would support.
03
Diagrams & Visual Aids
2 diagrams
Diagram 1: How Scores Spread Around a Mean
A normal (bell-shaped) distribution marked in standard deviations. In a normal distribution, about 68 percent of scores fall within one standard deviation of the mean and about 95 percent within two. Many ability scores are roughly bell-shaped, but not all: reaction times usually have a longer tail of slow responses.
Diagram 2: Reaction Time and Letter Span in One Invented Class
Each dot is one of the 12 students in Source 6: reaction time across, letter span up. Dots toward the left are faster reactions. Invented data, written for this page.
04
Homework Assignment
~30 min
Homework: Measuring and Explaining Differences
Directions: Part 1 uses Sources 1, 4 and 6. Quote every source you use with its paragraph number. Part 2 asks you to explain and to plan on paper only: do not test anyone.
Part 1: Reading and Computing (Problems 1-3)
Choose two of Cattell's ten tests in Source 1, one mainly physical and one mainly cognitive. For each, write an operational definition a modern researcher could use: the task, the score, its unit and which try counts.
In Source 6, compute the z-scores for the reaction times of student 5 and student 6. Show your work. Then explain what the sign of each z-score means for this measure, where a lower score is faster.
Source 4, paragraph 2 says that as many as 17 percent of teens have hearing-test features suggestive of noise-induced hearing loss. In an invented school of 1,200 students aged 12 to 19, about how many students would that be? Show your work, and explain why a survey estimate like this is not a way to judge any one student's hearing.
Part 2: Explaining and Planning (Problems 4-6)
Plan, on paper only, an experiment to test whether a week of practice improves simple reaction time. Name the groups, how people are assigned, the measure, two things kept the same, and the result that would support the idea.
A coach says: "Grip strength is just muscle." Use Source 2, paragraph 1 to write a reply of three or four sentences.
An invented ad says: "Our app raises your memory score by 30 percent in two weeks!" Use Source 5 to explain what evidence would be needed before believing it.
Rubric
Criterion
Full Credit (2 pts)
Partial Credit (1 pt)
No Credit (0 pts)
Measurement
Operational definitions name a task, a score, a unit and a rule for tries
One element missing
No usable definition
Computation
Problems 2 and 3 correct with work shown and the sign of each z-score explained
One error
Several errors
Evidence
Quotations with source and paragraph numbers support each claim about a source
Quotations without paragraph numbers, or one claim unsupported
No quotations
Responsible use
Keeps group results apart from claims about individuals, and plans are ethical and on paper only
Mentions limits without explaining them
Uses scores as labels for people
05
Quiz: 20 Questions
Interactive, with answers
Instructions
Sources 1 and 3 are printed in Direct Instruction, Source 6 in Guided Practice, and Sources 2, 4 and 5 in Independent Practice. Source 1 is used in Questions 1, 2, 7 and 15; Source 2 in Questions 3, 4, 15 and 16; Source 3 in Questions 5-7 and 19; Source 4 in Questions 8, 9, 15 and 17; Source 5 in Questions 10, 11, 15 and 18; and Source 6 in Questions 12, 13 and 19. Questions 14 and 20 need no printed source. Questions 1-14 are multiple choice; 15-20 are short answer.
Multiple choice: pick an option to check it. Short answer: write your answer, then reveal the model answer.
0 of 20 answered · 0 correct
Question 1 of 20 · Multiple Choice
According to Source 1, paragraph 1, what would make Cattell's tests much more valuable?
Answer: C
Cattell writes that the value "would be much increased should a uniform system be adopted, so that determinations made at different times and places could be compared and combined." That is the idea of a standardized procedure. A contradicts paragraph 2, where the first series is given to "all who present themselves." B and D are not in the source.
Question 2 of 20 · Multiple Choice
Which of Cattell's ten tests in Source 1 measures a mainly cognitive ability?
Answer: D
Repeating letters after one hearing depends on memory and attention, which Source 2 confirms: "Memory and attention may be tested" this way. A, B and C measure the force of a squeeze, the speed of an arm movement and the pressure that first feels painful, which are mainly bodily measures near the start of Cattell's list.
Question 3 of 20 · Multiple Choice
Why does Cattell say in Source 2, paragraph 1 that grip strength is not a purely physical quantity?
Answer: A
He writes that "it is, however, impossible to separate bodily from mental energy" and suggests experiments on "volitional control or emotional excitement and dynamometer pressure." C reverses what a right-handed person would usually show and is not in the source. D contradicts the whole description of the instrument.
Question 4 of 20 · Multiple Choice
In Source 2, paragraph 1, Cattell allows two trials with each hand and records the maximum. What does this procedure help with?
Answer: D
Recording the best of several tries reduces the chance that one poor attempt, for example from a bad grip, is taken as the person's ability; it is a step toward reliability. A would make the scores less accurate. B misreads the procedure, which records each hand. C is impossible: repeated tries vary.
Question 5 of 20 · Multiple Choice
According to Wissler's reasoning in Source 3, paragraph 1, what would show that a test measures a general ability?
Answer: B
"If a test is general, then its results should correlate with many other special tests." A describes the opposite case, which Wissler says would mean "two entirely independent forms of activity." C and D describe other features of scores that do not show generality.
Question 6 of 20 · Multiple Choice
What does Wissler conclude in Source 3, paragraph 5 about the marks students earned in their college classes?
Answer: B
Conclusion 3: the markings "correlate with themselves to a considerable degree but not with the tests made in the laboratory." C reverses both parts. A wrongly links marks to the physical tests. D contradicts the first half of the conclusion.
Question 7 of 20 · Multiple Choice
Taken together, what do Wissler's conclusions suggest about Cattell's plan in Source 1?
Answer: D
Wissler found that the laboratory tests did not correlate with class marks (conclusion 3) and that the mental tests showed "little intercorrelation" (conclusion 1). So the simple tests did not work as a measure of general ability. A contradicts conclusion 3. B contradicts conclusion 2, which says physical tests correlated "only to a very slight degree" with the mental tests.
Question 8 of 20 · Multiple Choice
According to Source 4, paragraph 3, which sounds are unlikely to cause hearing loss, even after long exposure?
Answer: B
"Sounds at or below 70 A-weighted decibels (dBA), even after long exposure, are unlikely to cause hearing loss." C is the level the source warns about: "long or repeated exposure to sounds at or above 85 dBA can cause hearing loss." A wrongly treats 85 dBA as a safe ceiling.
Question 9 of 20 · Multiple Choice
Source 4, paragraph 2 says that at least 10 million U.S. adults under 70, or 6 percent, have hearing-test features suggesting noise-induced hearing loss. About how many adults under 70 does that imply in all?
Answer: C
If 10 million is 6 percent, the whole group is 10,000,000 / 0.06, which is about 166.7 million, or about 167 million. A multiplies 10 by 6. B divides by 0.6 instead of 0.06. D is more than three times the correct total, larger than the population of the whole country.
Question 10 of 20 · Multiple Choice
According to Source 5, paragraph 4, what did the ACTIVE trial find?
Answer: A
"The sessions improved participants' mental skills in the area in which they were trained with evidence suggesting these benefits persisted for two years." B overstates: the benefit was in the trained area. D contradicts the source, since the participants were "65 and older."
Question 11 of 20 · Multiple Choice
What does Source 5, paragraph 5 say about commercial brain-training apps?
Answer: C
"There is currently not enough evidence available to suggest that computer-based brain training applications offered commercially have the same impact on cognitive abilities as the ACTIVE study training." A reverses this. B and D are not in the source.
Question 12 of 20 · Multiple Choice
In Source 6, student 2 has a reaction time of 244 ms. What is student 2's z-score?
Answer: A
z = (244 - 220) / 20 = 24 / 20 = 1.2. Because a lower time is faster, a positive z-score here means slower than the class average. B is the raw difference in milliseconds before dividing by the SD. C divides by 200 instead of 20. D divides the score itself by the SD (244 / 20), skipping the mean.
Question 13 of 20 · Multiple Choice
In Source 6, reaction time and letter span correlate at r = -0.36. Which statement fits that result best?
Answer: B
A negative r means higher reaction times (slower) went with lower spans, so faster students tended to have somewhat larger spans; -0.36 is a modest tendency, not a rule. A ignores the many exceptions visible in Diagram 2. C treats a correlation as a cause. D reverses the direction and overstates the strength.
Question 14 of 20 · Multiple Choice
Invented case: two large groups of students differ in average grip strength by 2 kg, and the standard deviation inside each group is 6 kg. What can you say about one student from each group?
Answer: C
A 2 kg difference in means is small next to a 6 kg spread inside each group, so the groups overlap heavily and either student could be stronger. A treats a group average as a fact about an individual. B jumps to a cause the data cannot show. D confuses overlap with being unmeasurable.
Question 15 of 20 · Short Answer
Using Sources 1-5, identify two different roles psychological science plays in understanding differences in abilities. For each role, give one example about a cognitive ability or one about a physical ability, so that both kinds appear, and cite the source and paragraph.
Model answer: (1) Measuring: Cattell proposed giving the same tests by "a uniform system" so results could be compared (Source 1, paragraph 1); his letter test measures a cognitive ability, memory (Source 2, paragraph 2). (2) Explaining what changes abilities: Source 4 shows that loud sound "can damage sensitive structures in the inner ear" (paragraph 1), so some differences in a physical ability, hearing, come from exposure. Other good answers: relating abilities with correlation (Source 3) or testing whether training changes abilities (Source 5, paragraph 4). Rubric: 1 point for each correctly named role; 1 point for each example with a citation; both a cognitive and a physical ability must appear.
Question 16 of 20 · Short Answer
Read Cattell's description of the letter test in Source 2, paragraph 2. What exactly does the test score, why might it test "Memory and attention" at once, and what is one way to make the procedure more reliable?
Model answer: The score is "the maximum number of letters which can be grasped and remembered" after hearing them once at two per second. A person must attend to each letter as it is spoken and hold the sequence in memory, so a low score could come from lapses of attention, from limited memory or from both. To make it more reliable, use a recorded voice for the same speed and clarity for everyone, give several lists at each length, and score the longest length repeated correctly on most tries. Rubric: 1 point for the score; 1 point for the two abilities; 1 point for a workable reliability change.
Question 17 of 20 · Short Answer
Source 4 gives two kinds of numbers: sound levels in paragraph 3 and an estimate for teens in paragraph 2. Explain what each kind of number adds to our understanding of why people differ in hearing.
Model answer: The sound levels turn a vague warning into a measured boundary: sounds "at or below 70" dBA are unlikely to cause loss, while long or repeated exposure "at or above 85 dBA can cause hearing loss." That lets researchers link differences in hearing to measured exposure. The teen estimate, "as many as 17 percent," shows that such differences can begin young and are common enough to matter for a whole population, which is why prevention is aimed at teenagers. Both numbers come from measurement, and neither tells us about any one student's ears. Rubric: 1 point for the sound levels with a quotation; 1 point for the teen estimate with a quotation; 1 point for the population, not individual, point.
Question 18 of 20 · Short Answer
Source 5, paragraphs 2 and 3 describe one study of older adults who learned quilting or digital photography, and then a comprehensive report. Why does the source treat the comprehensive report as more important than the single study?
Model answer: One study can be unusual because of its sample, its methods or chance. A comprehensive report reviews "the design and findings of these and other studies" together, so it weighs all the evidence and can notice weak designs. Because the report "did not find strong evidence" of lasting benefits, the single study's result should not be treated as settled. The source adds that research is needed "in large numbers of diverse older adults." Rubric: 1 point for the weakness of single studies; 1 point for what a review does; 1 point for a quotation.
Question 19 of 20 · Short Answer
A student says: "Source 6 proves that our class has fast thinkers and slow thinkers, so the teacher should seat them in separate groups." Give three reasons, from the lesson, why this conclusion is not justified.
Model answer: (1) Reaction time is a speed-of-response measure, not a measure of thinking in general; Wissler found that such laboratory tests did not even predict college marks (Source 3, paragraph 5). (2) The correlation of -0.36 with letter span is modest and comes from only 12 students measured once, so it could easily change with more data. (3) Using a single score as a label for a person, and sorting people by it, is the kind of misuse the fifth role of psychological science is meant to prevent; scores describe performance on one task on one day. Rubric: 1 point for each distinct, accurate reason.
Question 20 of 20 · Short Answer
In 1923 Carl Brigham used test scores to rank immigrant groups, and in 1930 he withdrew his conclusions. Describe two safeguards that psychological science uses today to keep ability measurement from being misused in this way.
Model answer: (1) Checking that a test is valid for each group it is used with, for example that it does not depend on knowing English or on familiarity with a culture's customs, before comparing groups. (2) Reporting the overlap and the spread inside groups, not just averages, and refusing to treat a group average as a fact about any individual. Other good answers: requiring that tests be used only for the purpose they were checked for, protecting the privacy of scores, and independent review and replication of claims. Rubric: 1 point for each safeguard with an explanation of how it prevents misuse.
0 of 20 answered · 0 correct
06
Frequently Asked Questions
10 Questions
What does D2.Psy.11.9-12 mean?
D2.Psy.11.9-12 asks high school students to identify the role psychological science can play in helping us understand differences in individual cognitive and physical abilities. It is an indicator in the C3 Framework's psychology companion (Appendix B), in the group on influences on thought and behavior.
What is the difference between a cognitive and a physical ability?
A cognitive ability involves mental work, such as remembering, attending or reasoning; a physical ability involves the body, such as strength, speed of movement or the senses. Many tasks mix both: even grip strength depends on effort, as Cattell noted in 1890.
What roles does psychological science play in understanding ability differences?
It measures abilities with defined, standardized tasks; describes how scores spread across people; tests which abilities go together; studies what changes abilities, such as practice, age and environment; and sets rules for using results fairly.
Is D2.Psy.11.9-12 about intelligence tests?
Partly, but it is broader. D2.Psy.11.9-12 covers both cognitive and physical abilities and the scientific methods used to study them. This lesson uses early mental and physical tests and current federal sources on hearing and cognitive training rather than focusing on IQ.
What is a z-score?
A z-score tells how many standard deviations a score is above or below the group's mean: z = (score - mean) / SD. It describes a score's place in one group, so it changes if the comparison group changes.
Why does the lesson use tests from 1890?
Cattell's 1890 tests and Wissler's 1901 check of them are a clear early case of psychological science testing its own tools. They are public domain. The page treats Cattell's hopes for simple tests as outdated and pairs the history with current federal sources.
How long does this lesson take, and can it be shortened?
The full plan takes 60-70 minutes. For a single 45-minute period, keep the Warm-Up, Direct Instruction with Sources 1 and 3, and the Guided Practice with Source 6, and assign Sources 2, 4 and 5 with the homework.
Can students test each other's abilities in class?
This lesson keeps all testing on paper. A teacher-led demonstration, if used, should be voluntary, anonymous and approved under school rules. Students never assess classmates' hearing, memory or health, and anyone with a personal concern should talk with a parent, school nurse or doctor.
What mistakes do students often make with D2.Psy.11.9-12?
Many students treat a correlation as a cause, read a group average as a fact about an individual, or forget that for reaction time a lower score is better. Others name a role of psychological science without an example. Asking "which role, which ability, and what is the evidence?" helps.
How does this indicator connect to other courses?
It builds on D2.Psy.5.9-12 (validity and reliability) and D2.Psy.10.9-12 (nature and nurture), and it uses the statistics of HSS.ID.A.4. It leads to D2.Psy.12.9-12, on how social and economic factors shape behavior.
07
Related Standards
6 standards
These standards connect to D2.Psy.11.9-12: prerequisites to review first, parallel standards at the same level, and next steps that build on it.
Before this lesson
D2.Psy.5.9-12Prerequisite
Explain how validity and reliability of observations relate to data analysis
Use critical thinking to become a better consumer of psychological knowledge
Lesson coming soon
Standard text: National Council for the Social Studies (NCSS), The College, Career, and Civic Life (C3) Framework for Social Studies State Standards: Guidance for Enhancing the Rigor of K-12 Civics, Economics, Geography, and History (Silver Spring, MD: NCSS, 2013). NCSS was not involved in the production of this lesson and does not endorse it.
