We study the impact of the Fridays for Future climate protest movement in Germany on citizen political behavior. Throughout 2019, large crowds of young protesters, the majority of whom were under voting age, skipped school to demand immediate climate change mitigation measures. We exploit cell phone-based mobility data and hand-collected information on nearly 4,000 climate protests to construct a spatially and temporally highly disaggregated measure of protest participation. Then, using various empirical strategies to address the issue of nonrandom protest participation, we show that the local strength of the climate movement led to more Green Party votes in state-level and national-level elections during 2019 and after. We provide evidence suggesting that three mechanisms were simultaneously at play: reverse intergenerational transmission of pro-environmental attitudes from children to parents, stronger climate-related social media presence by Green Party politicians, and increased coverage of environmental issues in local media. Together, our results suggest that environmental protests by those too young to vote may provide some of the impetus that is needed to push society toward overcoming the climate trap.