In this dissertation, I apply administrative data from Michigan's public schools to address crucial policy questions in the economics of education. In Chapter I, I shed light on the persistent effects of attending high-quality high schools by creating a value-added model that isolates each high school's effect on students' test scores, then matching the results to students' college transcripts to determine the relationship between high-school value added and first-year college grades. I find that students who attend high schools with one standard deviation higher value added receive first-year grades about 0.09 grade points higher than their otherwise-identical counterparts. These gains in college are not driven solely by math and English, ...