In 2016, Chicago Public Schools (CPS) enacted a computer science graduation requirement as a strategy to broaden participation in computing. Beginning with the 2016–2017 cohort of 9th graders, students have been required to complete one year of high school CS. The implementation of this policy has been supported by the Chicago Alliance for Equity in Computer Science (CAFÉCS), which is a research-practice partnership among CPS, The Learning Partnership, and the CS departments at DePaul University, Loyola University Chicago, and University of Illinois Chicago. Exploring Computer Science (ECS) is the course that most students complete to fulfill the graduation requirement (McGee et al., 2022). The ECS curriculum focuses on lessons that are culturally responsive and inclusive of the identities and interests of students as a means to foster a computing experience that is personally relevant to students (Margolis et al., 2012). The accompanying ECS professional development program is designed to support teachers in creating an equitable learning environment for students (Goode, Margolis, & Chapman, 2014). Completion of ECS professional development has been associated with increased learning outcomes (Boda & McGee, 2021a), decreased course failure (McGee, Greenberg, et at., 2018) and less teacher turnover (Shub & Maaz, 2021).

In 2012, CPS was the first school district to adopt the ECS curriculum and professional development program outside of Los Angeles, where it originated (Margolis et al., 2013). Subsequent research by CAFÉCS has pointed to apparent benefits of ECS for high school CS outcomes and provided support for the enactment of the CS graduation requirement. ECS is associated with student interest in pursuing additional CS coursework (McGee, McGee-Tekula, Duck, Dettori, et al., 2018) and students in ECS see similar growth in computational thinking performance regardless of student race, ethnicity, and gender (McGee, McGee-Tekula, Duck, McGee, et al., 2018). Two years after the enactment of the graduation requirement, the participation of African American and Hispanic students in AP Computer Science A (AP CS A) and AP Computer Science Principles (AP CSP) jumped significantly (Boda & McGee, 2021b). ECS may also serve as effective preparation for AP CS A: Students who took ECS prior to AP CS A were 3.5 times more likely to pass the exam with a score of 3 or higher than those who did not take ECS first (Boda & McGee, 2021b).

As the number of students completing one year of high school CS grew across the district, CAFÉCS initiated the Bridges to ECS project in 2017 with support from the National Science Foundation (DRL-1640215). The goal of the Bridges project was to infuse computational thinking activities into high school science classes and support this integration through professional development so science teachers could capitalize on the fact that a growing number of their science students would have had an introduction to CS. The CPS Office of Science was undertaking a multi-year initiative to develop high school science courses based on the Next Generation Science Standards. CAFÉCS supported the Office of Science with integration of computational thinking activities into specific units in the curriculum. The high school science curricula were officially released during the 2021–22 school year as part of CPS’s districtwide curriculum initiative, called Skyline (Koumpilova & Karp, 2023). 

As discussed above, prior research has found promising evidence that CPS’s curricular initiatives have benefits for CS educational outcomes. We extend this work by considering the possibility these initiatives have benefits that extend beyond CS. Specifically, we focus on spillover benefits to science courses, to test whether participation in CS courses promotes higher course grades in non-CS science classes. We then consider whether those spillover effects are moderated by teachers’ participation in ECS PD or by schools’ adoption of the Skyline curriculum. Using administrative data from CPS, we address the following questions:

1. Does taking CS courses promote students’ success (grades, likelihood of course passage) in non-CS science courses?
2. Are the effects of CS course-taking identified in question 1 larger for students who take ECS courses? 
3. Are the effects of CS course-taking different for students whose teachers have participated in ECS professional development?
4. Are the effects of CS course-taking different for students whose schools have adopted the Skyline curriculum?