To what extent does this movie criticize single-mothers?
Today (2016), our society is seeing a proliferation of single-mothers, especially in the black community (75% of births, or thereabouts). Tellingly, study after study has shown that growing up in a single-parent household massively increases the likelihood that a child will be a criminal, welfare recipient, drug-user, bully, high-school dropout, runaway, or suicide victim.
To what extent does "Boyz in the Hood" validate that point?
The three main boys "in the hood" are Tre, Doughboy, and Rickey. The latter two grow up under the supervision of a single-mother, and both grow up flawed -- Rickey is lazy, he is behind in his studies, and he is a father of a child-out-of-wedlock; and Doughboy is a hardened, belligerent, misogynistic criminal who spends most of his time drinking liquor with his boys and talking smack.
On the other hand, Tre grows up well. He leaves the car when Doughboy and others are going to commit murder, he waits to have sex because he "never lied to my father before," he has a job at a retail store, he doesn't sell drugs because "pops would kick yo' ass," and he ends up going to college at the end.
Plus, under the supervision of a single-mother, he was a troubled young man, as indicated by the fight in the movie's opening scene. Without Furious's influence, Tre likely grows up to be like Doughboy.
At the very least, you can agree that the movie emphasizes the importance of a father-figure in a child's life.