American Computer Science League (ACSL) organizes computer programming and computer science contests for K-12 schools, organizations and local groups.  The 2024-2025 school year will be our 47th year of continuous operation! Last year, about 8,000 students the United States, Canada, Europe, and Asia participated in the regular season competitions.

ACSL offers multiple divisions, providing an appropriate challenge for students of varying ages and abilities.  An unlimited number of students may compete in each contest.

Each season is divided into four contests, testing students on fundamental concepts in computer science, ranging from Number Systems to Boolean Algebra to Digital Electronics.  In the upper divisions, each contest also includes a problem to solve by programming using Python, C++ or Java.

Contests are administered online.  Team advisors facilitate students’ access to the online platform; the platform corrects the submissions and reports the scores to ACSL.  Online resources assist advisors to prepare their students for each competition.  Each topic on the Study Materials page is linked to the page of the ACSL Wiki that describes the topic in detail. 

At the end of the year, the top students are invited to compete in an online Finals competition.

The All About the ACSL webinar is a great resource for prospective advisors, students, and parents.  It was prepared by Nathan Gorski, the advisor of the Bay Coding Club


ACSL welcomes participation from all pre-college schools around the world.  If you are in Korea, China, or Vietnam, please read on for registration information; otherwise, use the form on this site to register.

In partnership with the Academic Consulting and Education group, schools in Korea should register at Students participate in the regular season contests, translated into Korean; scores are reported in the ACSL leaderboard and top students are invited to ACSL's end-of-year Finals.

ACSL has partnered with ASDAN China to administer the ACSL contests in ChinaStudents participate as individuals, and should register at Students take the ACSL contests translated into Chinese, and top students are invited to participate in ACSL's end-of-year Finals.

Students in Vietnam should reach out to our partner, Research Institute of Creative Education.  RICE administers the ACSL Contests to students as individuals, translating materials into Vietnamese.  Top students are invited to participate in ACSL's end-of-year Finals.  For more information, visit the RICE Facebook page or website.