The French Youth Experimentation Fund was established in 2009 to promote student achievement and social/professional integration of youth under 25. It provides funding for innovative local initiatives and rigorously evaluates their implementation and impacts to determine effectiveness before potential scaling up. Projects receive funding from the French government and private partners totaling 163 million euros from 2009-2013. The fund supports experimentation from associations, local governments, schools and other organizations, with independent evaluation of impacts on about 500,000 young beneficiaries. Evaluation methods emphasize randomized controlled trials where possible to identify causal effects of interventions on outcomes. Preliminary lessons show the importance of designing valid evaluation protocols and discussing evaluation approaches early to properly measure impacts.