Dinarte-Diaz, LelysGresham, JamesLemos, RenataPatrinos, Harry A.Rodriguez-Ramirez, Rony2025-09-032025-09-032025-09-02https://hdl.handle.net/10986/43666This paper provides insights into human capital investments during wartime by presenting evidence from three experiments of an online tutoring program for Ukrainian students amid Russia’s invasion of Ukraine. Conducted between early 2023 and mid-2024, the experiments reached nearly 10,000 students across all regions of Ukraine. The program offered three hours per week of small-group tutoring in math and Ukrainian language over six weeks and used academic and psychosocial tools to address student challenges at different intensities of disruption. Results show that the program led to substantial improvements in learning—up to 0.49 standard deviations in math and 0.40 standard deviations in Ukrainian language—and consistent reductions in stress—up to 0.12 standard deviations. High take-up and engagement rates were observed, and four mechanisms were identified as drivers of impact: structured peer interactions, improved attitudes toward learning, enhanced socio-emotional skills, and increased student investments. A complementary experiment using information nudges to increase parental engagement highlights challenges in promoting parental investments in a conflict setting. The program was cost-effective across all experiments, with benefit-to-cost ratios ranging from 31 to 56, and scalable given its reliance on existing infrastructure and teaching capacity.en-USCC BY 3.0 IGOUKRAINEWARTIMETUTORINGSTUDENT ACHIEVEMENTMENTAL HEALTHInvesting in Human Capital During Wartime: Experimental Evidence from UkraineWorking PaperWorld Bankhttps://doi.org/10.1596/1813-9450-11196