Computational thinking encompasses proficiencies in computer science and general problem-solving and can support students' learning across subject areas and success in science, technology, engineering, and mathematics (STEM) education and career pathways. To support students' STEM outcomes, many school districts are offering computer science education. Louisiana State University (LSU) received a federal Education Innovation and Research (EIR) grant (U411C190287) to develop and implement an Introduction to Computational Thinking (ICT) course. From fall 2020 through spring 2024, Education Northwest evaluated the implementation and impact of the ICT course. The impact study included high schools across East Baton Rouge Parish School System and urban and rural communities in Louisiana that serve large populations of students from economically disadvantaged backgrounds and students of color. Using a quasi-experimental design, this study found a positive impact of the ICT course on students' high school math achievement, including Algebra I state assessment scores and earning credit in an Algebra II or higher math course. The study recommends further scaling and evaluation of this computer science innovation to promote STEM outcomes for historically underserved students across the country.