Â鶹ÒùÔº

In a bid to engage more U.S. high school students in computer science, the College Board introduced a new Advanced Placement (AP) course in 2016: Computer Science Principles, which explores a range of topics in technology and computation, in contrast to the original AP course's strict focus on programming skills.

A new study by Stanford researchers, analyzing changes in the population of students taking AP computer science exams before and after the launch of the alternative course, shows a direct link between access to the course and a sharp increase in participation, with a sizable jump for traditionally underrepresented students.

After schools in the study began offering CS Principles, the number of students taking an AP computer science exam more than tripled overall, the researchers found. Exam counts for female, Black, or Hispanic students more than quadrupled.

What's more, schools that adopted the new course expanded participation in AP computer science without drawing students away from the original, programming-focused course. Access to the newer course also appears to have a spillover effect, increasing student participation in other AP subjects.

"Computer science education is valuable at so many levels, giving students a set of skills that apply across countless domains," said Daniela Ganelin, a doctoral student in education data science at Stanford Graduate School of Education (GSE), who coauthored the study with Thomas S. Dee, the Barnett Family Professor of Education at the GSE.

"Computing in general, and AI in particular, are so influential right now, and it's important for students to learn about it so they can understand it, use it responsibly, and be part of guiding its transformation over the course of their careers."

The analysis, April 10 in the Proceedings of the National Academy of Sciences, suggests that access to CS Principles could account for roughly two-thirds of the growth in AP computer science exams taken nationally over the past decade.

"We're finding a dramatic take-up of academically rich content at the high school level, without crowding out kids from taking the pre-existing course," said Dee, who is also a senior fellow at the Hoover Institution and the Stanford Institute for Economic Policy Research (SIEPR), and faculty director of the GSE's John W. Gardner Center for Youth and Their Communities. "This is a rare and compelling example of an educational reform that appears to be driving improvement on a nationwide scale."

A reflection of national trends

While the original AP computer science course focuses on teaching students how to write and test code in the Java programming language, the CS Principles course introduces students to programming as well as a wide range of concepts involving computers and technology, with an emphasis on creativity and collaborative problem-solving.

To assess the impact that access to the newer course has had on students' engagement with advanced-level computer science, the researchers drew on data from all public high schools in Massachusetts—the only state that researchers found publicly provides data on AP participation at the level of detail they sought, separated by subject, school, and student characteristics such as gender and ethnicity.

Massachusetts is a state with an unusually high AP participation rate to begin with, the researchers noted. "Because Massachusetts leans into AP so much, you might expect to see more of an effect there," Ganelin said. "On the other hand, if the state is well saturated with AP already, you might expect more dramatic effects in other states where the room for growth is higher."

The state's overall growth in AP exam-taking during the time period of the study mirrors trends in national data, the researchers said, which points toward the generalizability of their findings.

The researchers drew on data from the state's nearly 300 traditional public high schools over a 15-year period, from the 2006–07 school year through 2020–21. They found that after a school introduced CS Principles, its exam count in any AP computer science course jumped by an estimated 16 exams, more than tripling participation for the average school that adopted the course.

Analyzing the uptake for different demographic groups, the study found that the number of AP computer science exams taken by female, Black, or Hispanic students more than quadrupled: average female exam counts went from a baseline of 1.3 exams per school to about 6, while average exams for Black or Hispanic students went from 0.7 to about 3.

The new exams were concentrated in CS Principles, with no statistically significant drop in students taking the exam for the original AP computer science course.

The study also found that the initial spike after the course's introduction was followed by further growth over time, a trend the researchers said suggests that factors supporting students' participation—like staff capacity, the quality of the class, and awareness among students—strengthened after the course was adopted. That could be due in part to the standardization of content within the AP program, they said.

"When you have an intentionally designed course that's being offered in a relatively similar way throughout the country," said Dee, "it creates better opportunities for supporting teachers' capacity to deliver that content effectively, as well as student-focused learning supports."

The College Board has released descriptive findings in the past indicating similar patterns of growth, but the independent study by the Stanford researchers goes further to support a cause-and-effect relationship between increased participation and the introduction of CS Principles in individual schools.

A spillover effect

In addition to expanding participation in AP computer science, the launch of the new course appeared to boost engagement in other AP subjects. The study found that after introducing CS Principles, a school's total AP exam count grew by an estimated 33 yearly exams, representing a 9% increase for the average adopting school.

The gains were concentrated particularly in AP Environmental Science and English Language and Composition, which the study noted often serve as introductory college-level courses for their respective subject areas.

"I can imagine a situation where students taking one AP course might say, "I felt successful here," and want to take more in other subjects," said Ganelin, a former computer science teacher and curriculum specialist. "Or where a school might say, "We're having success in getting kids from a variety of backgrounds into this AP course. Let's see if we can encourage them to take others as well.'"

Given the advantages AP courses offer in preparing students for college and the ongoing challenge schools face in recruiting computer science teachers, the researchers said the AP program's standardized approach offers a promising model with economies of scale.

"There was a lot of work involved upfront in putting this course together, but now, if you're a principal or a teacher who wants to bring computer science to your school, this option exists," Ganelin said. "There are curriculum materials out there, there are training resources for teachers, so any principal can bring it to their school. And what we're seeing is that there's a good chance that if you offer it, kids will come. There will be take-up across demographic groups."