The purpose of this study was to investigate higher education mathematics departments' credit granting policies for students with high school calculus experience. The number of students taking calculus in high school has more than doubled since 1982 (NCES, 2007) and it is estimated that approximately 530,000 students took a calculus course in high school in the 2007-2008 school year (Bressoud, 2008). However, the high school experiences of these students may vary depending on the type and quality of the calculus program in which they participate. Since current commercially available placement tests still do not include calculus topics, it is unclear if common credit granting policies for students with high school calculus experience are accurately placing students. This research investigated two questions related to college mathematics departments' credit granting policies. First, the study determined what common practice is for departments to grant credit for Calculus I based on high school experience. Second, the research determined if there are differences in students' calculus achievement depending on the method by which credit was earned. To determine common practice, 244 mathematics departments were asked to complete a survey about their credit granting policies. A descriptive research methodology was used to report the results. A calculus-based placement test was administered to 143 college freshmen with high school calculus experience to determine their calculus achievement as they entered college. A causal-comparative design was used to compare calculus achievement based on earned credit status (did not earn credit, earned credit by AP Calculus AB Exam and earned credit by successful completion of a dual credit course). Survey results from 111 institutions (45.5% response rate) indicated that almost all colleges (93.5%) grant credit for Calculus I based on Calculus AB Exams scores while 59.0% of colleges grant credit for students who participate in dual credit programs. The results of the placement test indicated that students who earned credit by AP Calculus AB Exam had significantly higher calculus achievement than their dual credit counterparts, even when controlling for ACT Math sub-scores (p less than 0.01). In fact, no calculus achievement differences were found between dual credit students and students who did not earn college credit (p = 0.88). [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.]