The correct answer to this open question is the following.
The development of settlement houses affected urban American society in that it created new homes in different neighborhoods that offered so many services such as malls, new buildings for offices, parks, sports clubs, schools, shopping centers, and medical centers. The construction of better roads and highways.
Downtown in many large cities had become a crowed and unsafe space to raise a family. So many citizens decided to live in the suburbs, once urbanization had created new settlements. The problem was that this left some parts of the cities with poor neighborhoods where people did not have the above-mentioned facilities.