"Teach 25 years, not one year 25 times” is a teaching adage of unknown authorship. A teacher should learn something new each year, and this should be reflected in the lesson plan.

“Twenty-five years of teaching mean twenty-five different years, not one year twenty-five times” was cited in *Introduction to Education* (1955) by Harold R. Bottrell.

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*Introduction to Education:
Understanding Teaching Through Developmental Laboratory Experiences*

By Harold R. Bottrell

Harrisburg, PA: Stackpole Co.

1955

Pg. 133:

Twenty-five years of teaching mean twenty-five different years, not one year twenty-five times, Each and every year is full of many experiences — and this is what a teacher learns, and how he grows.

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*Advent Review and Sabbath Herald*

Volume 152, Part 1

1975

Pg. 2:

Someone once commented that a certain mediocre schoolteacher had taught school 20 years. To which someone else objected, “No, he hasn’t taught 20 years; he’s taught one year 20 times.”

21 July 1976, Amarillo (TX)

*Daily Times*, “Teachers Learn Uses For Papers in Class” by Nan Burk, pg. 2, col. 1:

“I know some teachers who have been teaching for 20 years,” she (Hope Shackelford—ed.) said. “But actually they’ve taught one year 20 times.”

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*Children Held Hostage, Or, Teachers’ Organizations Demands—Are They Justifiable?*

BY Phillip Carl Snyder and Earl E. Hogan

Zanesville, OH: Custom House Press

1981

Pg. 141:

In reality, many teachers who have taught 15 years have really taught one year 15 times. They teach the same thing over and over.

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*An Introduction to Teaching:*

A Handbook for Primary and Secondary School Teachers, Second Edition

A Handbook for Primary and Secondary School Teachers, Second Edition

Edited by Gill Nicholls

London: RoutledgeFalmer

2004

Pg. 17:

Developing an arsenal of teaching strategies, methods and styles is essential if you are to become an effective teacher. In short, the motto is: ‘Teach for 20 years; do not teach one year 20 times.’

Joe Clark

@DrJoeClark

Great teachers teach 35 years, not one year 35 times. #tlap #edchat

8:49 PM - 6 Jun 2014

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*101 Answers for New Teachers and Their Mentors:*

Effective Teaching Tips for Daily Classroom Use,Third Edition

Effective Teaching Tips for Daily Classroom Use,Third Edition

By Annette Breaux

New York, NY: Routledge

2015

Pg. 133:

I’ve often heard it said that some teachers teach 30 years, and others teach one year 30 times!

Jennifer Marten, PhD

@jenmarten

@romenendez14 It’s the old adage - teach 30 years not one year 30 times. Passion keeps us growing/learning. #txeduchat

9:01 PM - 28 Jun 2015