My dissertation investigates the effects of education policy on academic achievement. I focus on state and federal policies that seek to influence how teachers and school administrators educate their students, and I evaluate those policies' effects on academic achievement. Chapter 1 examines the effects of a compositional shift in a school's testing population brought about by the elimination of special education testing exemptions. The policy change forced each cohort within a school to add varying levels of generally low-achieving students to its testing pool, altering teachers' and schools' accountability incentives. I provide evidence that the elimination of exemptions caused significant increases in test scores for initially low-achieving students and narrowed the black-white test gap. Furthermore, I show that the measured effects were not caused by changes to classroom composition. Rather, accountability benefits from the elimination of testing exemptions flowed to low-achieving students because Texas' passing standard was low relative to the skills of its students. As school administrators and policy makers increasingly rely on standardized tests to determine teacher effectiveness, school funding, and the efficacy of educational policies, understanding how achievement scores are affected by outside factors has grown in importance. In Chapter 2, I use county-level variation in business cycles and achievement data for Texas 3-8 graders from 1995-2002 to better understand how business cycles impact student achievement. I find that a one standard deviation increase in the within-county unemployment rate causes a 0.04 standard deviation increase in achievement on Texas' state math exam. This result is robust to many choices of identification and specification, and I provide evidence that cross-county migration is not driving the results. One policy goal of school accountability is closing achievement gaps between minority and non-minority students. In Chapter 3 I use extensive Texas microdata to analyze whether the 1993 introduction of school accountability affected the black-white test gap across the distribution of initial student ability. I present evidence that the average test score gain associated with the introduction of accountability is higher for white students than for black students. I conclude that, despite Texas' inclusion of race-specific accountability standards, its policy did not narrow traditional achievement gaps. Accountability-driven increases in the gap can be explained largely by differences in racial composition and income across schools. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]