According to the headline in the NYT at the time. (The first sentence of the article includes mothers parenthetically.) It was the idea of the president of Hayden Publishing Company, James S. Mulholland, who said: "I got the idea for the tour from a sociological report I read a few years ago. It theorized that middle-class delinquency, particularly among boys, stems from their not knowing what their fathers do and so not having a model to pattern themselves after."
One of the pictures shows Mulholland with his own son, who "pronounced himself bored by everything but [the] big I.B.M. accounting machine":
We're told the accounting machine was an IBM 401, which I see dates back to 1933 and was "an early entry in a long series of IBM alphabetic tabulators and accounting machines... The 401 added at a speed of 150 cards per minute and listed alphanumerical data at 80 cards per minute." I'm looking for a picture of this thing the boy was prescient enough to love, but here's what a 402 looked like: