Seeking longitudinal evaluations of policies improving mobility amid inequality

[OliverH]

I'm an economics graduate student researching the long-term effects of income inequality on social mobility, specifically focusing on intergenerational wealth transfer and access to quality education. While the data on widening gaps is clear, I'm struggling to find compelling case studies of policy interventions that have demonstrably improved mobility metrics over a decade or more. For other researchers or policy analysts, what are the most rigorous longitudinal studies or regional examples you've encountered that show a measurable reduction in inequality's impact on opportunity? I'm particularly interested in evaluations of programs related to early childhood education, housing vouchers, or local job training initiatives.