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AMERICAN COUNCIL ON EDUCATION · ANNUAL, 1924–1954

The ACE Psychological Examination: a new test for every freshman class

For three decades the American Council on Education put out a fresh test for incoming college students, prepared by L. L. Thurstone and Thelma Gwinn Thurstone. It reported a quantitative and a linguistic score, and Thurstone argued that adult results belonged in percentiles, not mental ages.

AMERICAN COUNCIL ON EDUCATION
Psychological Examination for College Freshmen
1943 EDITION
L. L. Thurstone · Thelma Gwinn Thurstone
Title as catalogued for the Smithsonian's copy of the 1943 edition [1]. Re-set, not a facsimile.

A test that was rewritten every year

The Smithsonian says the test was published annually from 1924 to 1954 [1]. A biographical encyclopedia credits the Thurstones with 24 successive annual editions [2]. Thirty-one years and 24 editions don't match, so the strip marks only the years we can tie to a document. Select one.

1943The edition held by the Smithsonian, catalogued with both Thurstones as makers.[1]

Made by two Thurstones

L. L. Thurstone1887–1955
TrainingEngineering degree, Cornell, 1912; briefly in Edison's laboratory[1]
1923In Washington at the Institute for Government Research, writing manuals for objective civil-service exams[2]
1924–52University of Chicago[1]
The ACEWith Thelma Gwinn's help, prepared a test for selecting or classifying college students[2]
Thelma Gwinn Thurstone1897–1993
1923Master's degree, then a year at the Institute for Government Research[3]
ChicagoStatistician creating psychological tests for the American Council on Education[3]
1926Doctorate on test theory[3]
1948Full-time director of the Division of Child Study, Chicago public schools[3]

Two scores, not one

Later studies report results on the ACE's quantitative scale separately from the rest [4]. Six questions below feed a Q score or an L score, then a total.

Questions and section labels are ours. We haven't seen a full list of the ACE's own sub-tests, so none is claimed.
COUNTS TOWARD Q · ARITHMETICA train covers 180 miles in 4 hours. At that rate, how far does it go in 7 hours?
Choose an answer.
REPORT CARD
Q score0 / 2
L score0 / 4
Total0 / 6
Two people can share a total and still differ: one strong on Q, the other on L. That is what a split score is for.

Why a freshman got a percentile, not a mental age

In 1926 Thurstone pointed out that two different definitions of mental age were in use. He argued that neither worked for adults, and that test results should be given as percentile ranks or standard scores [2]. A college test, whose takers were all near-adults, is where that matters.

Illustration: a made-up freshman group with scores normally distributed, mean 100 and SD 20. Move the score to see its percentile.

84percentile rank
+1.00standard score (z)
—mental age: undefined for adults

References

  1. [1]Psychological Test, American Council on Education Psychological Examination for College Freshmen, 1943 Edition. National Museum of American History, 1990.0034.166.americanhistory.si.edu
  2. [2]Thurstone, L. L. International Encyclopedia of the Social Sciences, via Encyclopedia.com.encyclopedia.com
  3. [3]Thelma Thurstone. Wikipedia.en.wikipedia.org
  4. [4]Study using the ACE Psychological Examination for College Freshmen, citing Thurstone & Thurstone, Manual of Instructions, 1947 edition. The Journal of Educational Research, 1956.tandfonline.com
  5. [5]Louis Leon Thurstone. Wikipedia.en.wikipedia.org
HOW TO CITE THIS PAGE
What's Your IQ. (2026). ACE Psychological Examination for College Freshmen (1924–1954). In Historical IQ Tests Archive. Retrieved October 1, 2026, from /en/historical-iq-tests/ace-psychological-examination-1925
EDITORIAL RECORD
First published2026
Last reviewed1 October 2026
Sources5: the Smithsonian record of the 1943 edition, a social-science encyclopedia entry on Thurstone, two encyclopedia biographies, and a 1956 study that used the test
CorrectionsDates changed from 1925–1957 to the Smithsonian's 1924–1954. Removed: "the first national college admissions IQ test", "ancestor of the SAT", "discontinued in 1957 when the SAT became dominant", the GRE as descendant, Trabue as the source of a Completion section, and the six named sub-tests presented as the ACE's own.
Open questionsThe ACE's actual sub-tests by edition; how many editions there were (24, or one a year for 31 years); how colleges used the scores
Canonical URLwhats-your-iq.com/en/historical-iq-tests/ace-psychological-examination-1925

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Part of the Historical IQ Tests Archive. Editorial content under CC BY-SA 4.0. No items from any ACE edition are reproduced here.

Scored against today's adults. Just as Thurstone wanted.

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