"The best way to learn is to teach"

“The best way to learn is to teach” is an old saying; a teacher who can explain a subject and answer all questions about it has effectively learned the material. “No maxim is more ancient than that, what a person understands he can communicate, and that the best way to learn is to teach” has been cited in print since at least 1824.

American particle physicist and professor of physics Frank Friedman Oppenheimer (1912-1985) has been associated with the old saying since at least 1998, when the following was published in the magazine Science:

“Oppenheimer had a provocative approach to learning, which can be summarized by saying that the best way to learn is to teach, the best way to teach is to keep learning, and that what counts in the end is having had a shared, reflected experience.”

Wikipedia: Frank Oppenheimer
Frank Friedman Oppenheimer (August 14, 1912 – February 3, 1985) was an American particle physicist, professor of physics at the University of Colorado, and the founder of the Exploratorium in San Francisco. A younger brother of renowned physicist J. Robert Oppenheimer, Frank Oppenheimer conducted research on aspects of nuclear physics during the time of the Manhattan Project, and made contributions to uranium enrichment. After the war, Oppenheimer’s earlier involvement with the American Communist Party placed him under scrutiny, and he resigned from his physics position at the University of Minnesota.

Oppenheimer was a target of McCarthyism and was blacklisted from finding any physics teaching position in the United States until 1957, when he was allowed to teach science at a high school in Colorado. This rehabilitation allowed him to gain a position at the University of Colorado teaching physics. In 1969, Oppenheimer founded the Exploratorium in San Francisco, and he served as its first director. He lived in Sausalito, California, until his death in 1985.
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He was eventually awarded a grant from the National Science Foundation to develop new pedagogical methods, which resulted in a “Library of Experiments” — nearly one hundred models of classical laboratory experiments which could be used in aiding the teaching of physics to elementary school children (Oppenheimer was the one who made the often-referenced quote “the best way to learn is to teach”).

Hathi Trust Digital Library
Monitorial Instruction:
An address, pronounced at the opening of the New-York High-School
By John Griscom
New York, NY: Printed by Mahlon Day
1825
Pg. 107:
[Also Hathi Trust Digital Library, January 1824, The Westminster Review, pg. 52.]
[Reprinted 2 May 1826, Sentinel of Freedom, and New-Jersey Advertiser (Newark, NJ), “Monitorial Instruction,” pg. 2, col. 2.]
1. The first and essential principle of the new system of education is, that children teach each other. This, like many other important discoveries, is but the new application of an old truth; for no maxim is more ancient than that, what a person understands he can communicate, and that the best way to learn is to teach.

Hathi Trust Digital Library
24 August 1850, The Working Man’s Friend and Family Instructor, pg. 205, col. 1:
He said, “The readiest way to learn is to teach.”

Google Books
October 1900, American Ecclesiastical Review, pg. 340:
Then, besides, we all know the best way to learn is to teach.

Google Books
Little Journeys to the Homes of Great Philosophers
By Elbert Hubbard
East Aurora, NY: The Roycrofters
1904
Pg. 6:
He (Immanuel Kant—ed.) must have been an efficient youth, for before he was eighteen he realized that the best way to learn is to teach.

Hathi Trust Digital Library
Education for Character:
Moral Training in the School and Home
By Frank Chapman Sharp
Indianapolis, IN: The Bobbs-Merrill company
1917
Pg. 81:
They are an attempot to apply the principle which all of us know from our own experience but which few of us ever think of using, the principle, namely, that the most effective way to learn is to teach.

Hathi Trust Digital Library
Life of Thomas J. Jackson
By Mary L. Williamson
Richmond, VA: B. F. Johnson Publ. Co.
1918
Pg. 42:
He felt that by close study he could reach a far higher stage of mental power, and the position of professor gave him a chance to do this, for he knew that the best way to learn is to teach.

Google Books’
May 1920, The Green Book Magazine, “Teamwork” by Harold Cary, pg. 15:
“The best way to learn is to teach,” she told Phil. “This is why I’m so brazen about spending time with you.”

Hathi Trust Digital Library
College
By John Palmer Gavit
New York, NY: Harcourt, Brace & Co.
1925
Pg. 96:
The best way to learn is to teach.

Hathi Trust Digital Library
Naval Reserve Guide
By Guido F. Forster and Edwin Laird Cady
New York, NY: Cornell Maritime Press
1943
Pg. 96:
Since the best way to learn is to teach, and since teaching is one of the strongest forms of leadership, the officers as well as the men were developed by these methods.

Google Books
The Psychology of Teaching
By W. Lambert Gardiner
Monterey, CA: Brooks/Cole Pub. Co.
1980
Pg. 336:
It has taken years of research to stumble on what we have been saying (if not believing) for a long time — the best way to learn is to teach — and to recommend what we have had for a long time — the one-room schoolhouse.

Google Books
July 1983, The Rotarian, pg. 14, col. 1:
Robert Hutchins used to say that the best way to learn is to teach someone else. This is a key principle in the twelfth step of Alcoholics Anonymous: carrying the spiritual message to other alcoholics.

Science magazine
Science 26 June 1998:
Vol. 280 no. 5372 pp. 2054-2055
ESSAYS ON SCIENCE AND SOCIETY
Putting Science in the Hands of the Public
Goéry Delacôte
(...)
At the Exploratorium, Oppenheimer put his own, unorthodox spin on the Palais’s program by inviting younger, and therefore less educated, students (high school and early college years rather than graduates) to be the key players. For 12 weeks, Explainers work part-time, for minimum wage, helping visitors to the museum. Oppenheimer had a provocative approach to learning, which can be summarized by saying that the best way to learn is to teach, the best way to teach is to keep learning, and that what counts in the end is having had a shared, reflected experience.

Google Books
Key Marketing Skills
By Peter Cheverton
Sterling, VA: Kogan Page Limited
2004
Pg. 375:
It is often said that the best way to learn is to teach.

OCLC WorldCat record
Rich Dad’s teach to be rich : because the best way to learn is to teach what you want to learn and the best way to get rich is to help others become rich
Author: Robert T Kiyosaki; Sharon L Lechter
Publisher: [S.l.] : Rich Press, ©2006.
Edition/Format: Book : English
Summary: Book explains that the solution to becoming rich is by teaching others to be rich.