TRAINS, Unit Study Books (No. 301). Kalmbach Publishing Co., American Education Press, Inc., Columbus, Ohio, 1934.
 
Trains Booklet
Unit Study Book #301
Vintage from the 1930s
 
Prior to WWII, The Educational Printing House, Inc. of Columbus, Ohio printed short, small paperback pamphlet books in the Unit Study Book series. The originals were often reprinted by The American Education Press, Inc. of Columbus, Ohio through 1940. The authors of the Unit Study Book series books were elementary school educators and frequent contributors of the My Weekly Reader, a popular children's periodical also published by the American Education Press, Inc.
 
After WWII, the Unit Study Book Series became the Little Wonder Series published by Charles E. Merrill Publishing Co. of Columbus, Ohio and New York, NY. The Little Wonder books were marketed as a collection of the small booklets in a metal, hinged box as a library of 50 booklets. 

Orange cover with illustrated drawing and photographic illustrations inside. Just light wear with few corner creases. About 8 x 5 with 36 pages. Scarce!