The attitudes toward violence, Native Americans, and blacks depicted in Abe Lincoln Grows Up may concern parents and teachers. Sandburg frequently makes violence sound attractive: "Three boys teased him one day...they would not be satisfied till he had punched their noses." Some descriptions of Mike Fink's and Andrew Jackson's escapades may be viewed as glorifications of physical violence. When Sandburg writes about social injustice, such as the treatment of Native Americans and slaves, he never offers any comment of his own. Some critics defend him on the grounds that the irony implicit in the situations amounts to a form of recrimination, but young readers may not recognize the irony as such and may instead interpret the lack of comment as moral neutrality or, worse yet, as approval. Most of these problems occur because the work was written over sixty years ago, when the collective social conscience was not as well-developed as it is now. The realization that moral standards change rapidly in American society is an important part of education today.

The old-fashioned virtues of hard work, family values, and love for God and one's country are certainly prominent in the biography, but Sandburg's streak of realism tempers any overoptimism about the advantages of living in accordance with these standards. The author points out more than once, "The wilderness is careless," and he quotes the folk proverb, "The cowards never started and the weak ones died by the way."