Non-Technical Summary:
When interventions target cognitive skills or behaviors, capacities or beliefs, promising impacts at the end of the programs often disappear quickly. Our paper seeks to identify the key features of interventions, as well as the characteristics and environments of the children and adolescents who participate in them that can be expected to sustain persistently beneficial program impacts.
We describe three such processes: skill-building, sustaining environments and foot-in-the-door. We argue that skill-building interventions should target “trifecta” skills: skills that are malleable, fundamental, and would not have developed eventually in the absence of the intervention. The sustaining environments perspective views the quality of environments subsequent to the completion of the intervention as crucial for sustaining early skill advantages. Successful foot-in-the-door interventions equip a child with the right skills or capacities at the right time to avoid imminent risks (e.g., grade failure or teen drinking) or seize emerging opportunities (e.g., entry into honors classes). These three perspectives generate both complementary and competing hypotheses regarding the nature, timing and targeting of interventions that generate enduring impacts.
We outline three of the most promising intervention approaches, given the three routes to impact persistence that we have described above. An obvious one is to ensure that human-capital interventions successfully target what we refer to as “trifecta” skills, behaviors and beliefs – which can be changed, are fundamental for later success, and would not have developed in the absence of the intervention.
A second promising intervention strategy might rely on beneficial peer, classroom and other sustaining environmental effects generated by interventions conducted at scale. On the policy side, subsequent peer and classroom dynamics might justify universal preschool interventions targeting non-trifecta academic and socioemotional skills because they would support higher-level instructional content in subsequent grades.
A third intervention approach is to target important but difficult-to-change skills or behaviors with very intensive interventions for subgroups of children most in need of help and least likely to develop those skills in the absence of the intervention.