This quantitative ex post facto study investigated the effects of career academies on academic achievement and college readiness. A total of 1,206 12th-grade participants (196 career academy and 1,010 nonacademy students) were used in this study. These participants came from six high schools located in one large urban school district. Each of the six high schools housed a different career academy. The purposes of this study were (a) to determine if there was a significant difference in ACT scores between students enrolled in a career academy and students who were not enrolled in a career academy, while controlling for the students' eighth-grade EXPLORE scores and (b) compare the ACT performance of the different academies. Five Analysis of Covariance (ANCOVAs) and two Simple Main Effects tests were used to analyze the data. This study found that career academy students scored statistically higher on the science subtest of the ACT than nonacademy students only when students scored at the low level on the science EXPLORE subtest. In the areas of English and math, there was no statistical difference between academy and nonacademy students' academic achievement as measured by the ACT subscores. When comparing the academies to each other, one academy scored statistically lower than all the other academies in this study in all ACT tested areas. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]