A recent pick-up a News Letter Advertizing piece 4 pages 12" by 17" with insight on the activities at the Academy of Sport. Printed in early May/June is my guess based on content. 
The Academy of Sport offered the public an interesting venue to see awards and trophy's from teams and athletes from the world of sports. The Academy also offered classes in Baseball & Football with professional players and managers as instructors. Each preregistered student would received a Laurel Card for their precipitation. The Laurel Cards were signed by 76 baseball instructors, 11 Managers 65 Players, from 1939 to1940. 
According to Christy Walsh "the Laurel Card bears the name of a student and the name of the instructor of the day, thus providing a souvenir more valuable and personal than the ordinary autograph." 
In addition radio broadcasts by NBC on Saturday with Bill Stern  and on Wednesday Mutual Broadcasting with Stan Lomax covered the special activities.
Most interesting is a article noted as Roll Call The Academy of Sport's Honor Roll of Mangers and Players and potential Laurel Card signers. Copied from the news letter April 30, to June 26, 1939 not sure if this list actually participated as instructors of the day. 
Sports at the New York WORLD'S FAIR
PHILADELPHIA  ATHLETICS
Connie Mack
NEW YORK YANKEES
Joe McCarthy, Joe DiMaggio, Lefty Gomez, Red Rolfe, 
Bump Hadley, Art Jorgens, Jake Powell, George Selkirk
 
NEW YORK  GIANTS
Bill Terry, Carl Hubbell, Mel Ott, Zeke Bonura,  
Harry Danning, Travis Jackson
 
CHICAGO  CUBS
Gabby Hartnett, Augie Galan, Stanley Hack, Glen Russell, 
Jim Gleeson  
PHILADELPHIA  PHILLIES
Doc Prothro, Pinky Whitney, Virgil Davis 
PITTSBURGH PIRATES
Pie Traynor, Paul Waner, Lloyd Waner, Chuck Klein
CLEVELAND  IDIANDS
Oscar Vitt, Bob Feller, Jeff Heath
ST.LOUIS  CARFINALS
Ray Blades, Pepper Martin, Joe Medwick
CINCINNATI  REDS
Bill McKechnie. Johnny Vander Meer, Bill Werber, 
Hank Gowdy
DETROIT  TIGGERS
Pinky Higgins. Earl Averill, Merv Shea
ST.LOUIS  BROWNS
Fred Haney, George McQuinn, Myril Hoag 
BROOKLYN  DODGERS 
Leo Durocher, Ernie Koy, Dolph Camilli, Van Mungo, 
Tuck Stainback, Babe Phelps, Al Todd, Cookie Lavagetto
WASHINGTON  SENATORS
Dutch Leonard, Ossie Bluege, George Case
Check out my web site 
www.1939baseball.com