No one would deny that some of us have had advantages over others. But it's a long way from saying that "environment matters" to saying what about your environment matters.
In both politics and charity, we hear many proposed "solutions" for poverty and inequality. Most of these solutions have been tried. Very few have been tested. And of those that have been tested, many just don't work.
Examples
Education. The New York City Voucher Experiment offered scholarships to low-income students, so they could attend the school of their choice. The effects were small to nonexistent, as we discuss here.
Childcare and job training. The Comprehensive Child Development Program brought case managers to the homes of low-income families to offer them direct counseling and refer them to local services (job training, childcare, etc.) The program had little or no effect on families' economic conditions or children's cognitive and social development, as we discuss here.
Substance abuse prevention. The D.A.R.E. program consists of 10-20 weekly hour-long sessions in which police offer speak to middle-school students aiming to reduce substance abuse. When studied formally, the program did not show a significant effect on subsequent drug use among participants. Details here (from Evidencebasedprograms.org).
Afterschool programs. The 21st Century Community Learning Centers program funds after-school programming in high-poverty elementary- and middle- schools providing time for homework, an additional educational activity, and access to other arts or sports programs. An evaluation of elementary-schools in the program found no effect on students' outcomes. Details here (from Evidencebasedprograms.org).
More examples. In a guest post on the GiveWell Blog, David Anderson of the Coalition for Evidence-Based Policy estimates that 75% of rigorous evaluations show weak effects, no effects, or negative effects, and gives several more examples including educational software and family literacy programs.
There are also success stories, such as the Nurse-Family Partnership. A larger list of well-studied programs is available via the Coalition for Evidence-Based Policy, though these programs are not necessarily connected to particular charities.
Most programs have never been evaluated
The programs listed above are among the few social programs that have been given serious, careful study. Most charities' programs have simply never been seriously evaluated at all.