“Don’t take any wooden money/nickels” means “don’t be cheated/duped.” “Don’t take any wooden nickels or bad checks” was cited in 1903 and “Don’t take any wooden money” was cited in 1904.
 
Wooden money was used in the United States during Colonial times and in the depression of the 1930s, although it was not issued when the saying originally became popular. Wooden nickels were issued around the 1900s as promotions for a merchant or a bank.
 
   
Wikipedia: Wooden nickel     
In the United States, a wooden nickel is a wooden token coin, usually issued by a merchant or bank as a promotion, sometimes redeemable for a specific item such as a drink.
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An American adage, “Don’t take any wooden nickels” is considered a lighthearted reminder to be cautious in one’s dealings. This adage, too, precedes the use of wooden nickels as a replacement currency, suggesting that its origins lie not in the genuine monetary value of nickels but rather in their purely commemorative nature.
 
Penn Ohio Wooden Money Collectors
History - Wooden Money
ORIGIN OF WOODEN MONEY
Scrip dates back to Colonial times as a money substitute for Americans in cash-poor times.  Tokens circulated widely in place of coins during the Panic of 1837 and the Civil War.  Banks also pooled their resources to issue clearinghouse certificates during financial crises in 1893 and 1907.
 
But nothing shook this country’s financial system as hard as the depression that began with the stock market crash of 1929.  Rather than bounce back after an ordinary down cycle, as many business and government leaders at first thought would happen, the economy spiraled out of control.  Credit shut down as banks called in all their loans.  Factories closed.  People stopped spending.  And money vanished from circulation.
 
The first wave of bank failures began in 1931, which also witnessed the first attention-getting effort to circulate scrip.
 
Wiktionary: don’t take any wooden nickels
Etymology
circa 1930s. Depression-era expression relating to privately minted wooden tokens which resembled coins but were used as commemoratives or promotional items.
Proverb
don’t take any wooden nickels
1. (US, dated) Do not permit yourself be cheated or duped; do not be naive.
 
(Oxford English Dictionary)
wooden nickel  n. U.S. slang a worthless or counterfeit coin; chiefly in fig. phr. to take a wooden nickel and varr., to be swindled or fooled.
1927   Amer. Speech 3 132   [College slang.] Not to ‘take any wooden nickels’, in other words, to be alert.
1937   L. Hellman Diary 23 Oct. in Unfinished Woman (1969) viii. 100   Luis and I got to Madrid. He said I was not to take any wooden nickels.
wooden money U.S. slang = wooden nickel n.
1915   C. Mathewson Catcher Craig ii. 25   He was instructed..not to take any wooden money.
1922   S. Lewis Babbitt v. 67   S’long! Don’t take any wooden money.
 
Chronicling America
5 February 1903, Phillipsburg (KS) Herald, pg. 4, col. 3:
Don’t take any wooden nickels or bad checks.
 
19 May 1904, Idaho Statesman (Boise, ID),  “Mixup Over Game Licenses,” pg. 6, col. 3:
“Don’t take any wooden money.”
 
Chronicling America
25 February 1905, The Evening Star (Washington, DC), pg. 2, col. 3:
Touched Upon the Raw>
From the Louisville Courier-Journal.
McFlub—“Say, that man Gotrox you introduced me to is a dern peculiar chap. On parting I said to him, “Good-bye, old man, don’t take any wooden money,’ and, by George, he wanted to fight!”
Sleeth—“Great Scott! Don’t you know his business?”
McFlub—“No; what is his old business?”
Sleeth—“Man, he’s a Cleveland banker.”
 
Google Books
March 1905, The Railroad Telegrapher (St. Louis, MO), pg. 340, col. 1:
We will hope that all of the boys will not take any wooden money while away on their “annual vacation.”
 
Chronicling America
16 May 1906, The Salt Lake Tribune (Salt Lake City, UT), “‘Home Run’ Marshall Arrives in Zion,” pg. 9, col. 5:
Jack sends his regards to the bunch and hopes they will not take any wooden nickels.
 
30 November 1907, Kalamazoo (MI) Gazette, “There’s No Panic in ‘Land of Dollars,’” pg. 3, col. 4:
Keep your nose clean and don’t take any wooden nickels.
 
OCLC WorldCat record
“… AND DON’T TAKE ANY WOODEN NICKELS”
Author: John Johnson Affiliation: Associate Editor of Supervisory Management, published by the American Management Association, New York City, New York. This article appeared originally in the November, 1956, issue of Supervisory Management.
Edition/Format: Article Article : English
Publication: Journal of Communication, v7 n3 (September 1957): 129-135
Database: Wiley Online Library
 
OCLC WorldCat record
Don’t take any wooden nickels : an inquiry into and application of the creative process in your life
Author: James William Walsh
Publisher: Ashland, Pa. : Underbridge, ©1994.
Edition/Format:   Book : English
 
OCLC WorldCat record
Don’t take any wooden nickels
Author: Mindy Starns Clark
Publisher: Eugene, Or. : Harvest House, ©2003.
Edition/Format:   Book : Fiction : English
Database: WorldCat
Summary:
“Working to provide quality work clothes to women who can’t afford to buy their own, Callie becomes involved with one young woman trying to come out of drug rehabilitation - just as she’s charged with murder. What appears to be a routine murder investigation in her sleepy waterside village suddenly becomes complicated amid international intrigue, cutting-edge technology, and deadly deception. In a desperate moment at what could be the end of her life, Callie cries out to the God who is as close as a whispered prayer.”—Publisher description.
 
Urban Dictionary
Don’t Take Any Wooden Nickels
Don’t let anyone get over on you! Be alert and aware of shady people. (Often said as a goodbye)
Talk to you later, don’t take any wooden nickels!
by angelas3656 June 15, 2012