
A prophetic article entitled The Laboring Classes appeared in The Boston Quarterly Review in 1840 at the very moment Horace Mann’s crowd was beating the drum loudest for compulsion schooling. Its author, Orestes Brownson, charged that Horace Mann was trying to establish a state church in America like the one England had and to impose a merchant/industrialist worldview as its gospel. "A system of education [so constituted] may as well be a religion established by law," said Brownson. Mann’s business backers were trying, he thought, to set up a new division of labor giving licensed professional specialists a monopoly to teach, weakening people’s capacity to educate themselves, making them childlike.
A century and a half after The Laboring Classes was published, Cornell labor scholar Chris Clark investigated and corroborated the reality of Brownson’s world. In his book Roots of Rural Capitalism, Clark found that the general labor market in the Connecticut Valley was highly undependable in the 1840s by employer standards because it was shaped by family concerns. Outside work could only be fitted into what available free time farming allowed (for farming took priority), and work was adapted to the homespun character of rural manufacture in a system we find alive even today among the Amish. Wage labor was not dependent on a boss’ whim. It had a mind of its own and was always only a supplement to a broad strategy of household economy.
This is almost true, but gets some key things mixed up. I do think it was a common sentiment among native born white Americans that industrial wage labor was degrading and beneath them (see Orestes Brownson's The Laboring Classes for an example), I do think that the school system was shaped to make people more docile and less entrepreneurial, and I do think that many reformers intended for most kids going through it to end up doing industrial wage labor, but I don't think it was done to solve a labor shortage. The waves of mass immigration that occurred between 1830 and 1920 meant that despite the common view that wage labor was antithetical to the American way of life embodied by the autonomous farmer, American industry was never in short supply of labor.