The Advanced Placement (AP) program represents a critical element in Houston Independent School District's (HISD's) efforts to inject rigor into the high school classrooms. Since 2009, the AP course offerings in HISD have been vastly expanded, with more campuses offering a wider selection of AP courses that exposes a larger percentage of the high school population to academic rigor. Significantly more HISD students are taking and completing AP courses, taking and passing AP Exams, and earning AP Awards now than before 2009. Among the highlights of AP in 2015-2016 are: (1) The number of high school students taking at least one AP Exam increased by 3 percent to 14,416 in 2015-16 from 13,929 in 2014-15; (2) The number of AP Exams taken by high school students increased by 7 percent to 26,868 in 2015-16 from 25,127 in 2014-15; (3) The number of AP Exams scored 3 or higher increased by 6 percent to 8,765 in 2015-16 from 8,277 in 2014-15; however the proportion of exams scored 3 or higher remained constant at 33 percent in both 2014-2015 and 2015-16; (4) History and Social Sciences represented the largest category among the six AP categories with 47 percent of all AP Exams taken by high school students, followed by 23 percent in Science, Technology, Engineering, and Mathematics (STEM); and (5) Enrollment in AP courses remained constant at 37 percent in 2015-16 compared to the previous year for students enrolled in grades 10-12.