A stable and positive family structure is necessary, but the single-parent is running into a strong head wind of gang influence/presense. I will admit that I haven't read into the Chicago problem, but I think the gang power must be crippled before any other positive programs could take hold.
I'm assuming that the gangs are recruiting kids (12-18) to fill the ranks. Probably through fear and coercion. A single mom (or aunt, uncle, grandparent) is going to have a tough time sheltering their child from gangs on the street, in the stores, maybe even in your building.
Kids need schools and after school programs. But instead of fully paid by taxpayers, I would get Corporations to match funds. School vouchers, after school programs, job training for the parents. While this is going on, Rahm needs to bust up the gangs. He needs a Chicago surge, his version of "New Way Forward".