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The Ultimate Guide to the American Computer Science League

For anyone experienced in computer science, or recently became interested in programming systems and want to learn more, the American Computer Science League is the perfect competition circuit for you.

What is the American Computer Science League?

The American Computer Science League (ACSL) is a non-profit organization that promotes computer science education and programming skills among students in the United States. The organization offers a series of annual contests and competitions for students at various grade levels, ranging from elementary school through high school. The ACSL's contests cover a range of computer science topics, including programming, algorithms, data structures, and computer organization. These contests are designed to challenge and inspire students, while also helping them to develop critical thinking and problem-solving skills.

In addition to its contests, the ACSL also offers resources for teachers and students, including practice problems, online courses, and instructional materials. The organization aims to foster a love of computer science and technology among young people, and to prepare them for future careers in these fields.

The ACSL has existed since 1978, and is now a worldwide competition for the best young computer scientists, reaching 300 schools and 1,700 students participating in the end-of-season finals last year.

Why Should You Participate in the American Computer Science League?

There are several reasons why you might choose to participate in the American Computer Science League contests:

  1. Develop Programming and Problem-Solving Skills: ACSL contests are designed to challenge students and help them develop their programming and problem-solving skills. These skills can be valuable in many fields, including computer science, engineering, and mathematics. Thus, from any age, you are able to develop your technical skills and knowledge and further your interest in computer science.

  2. Preparation for Competitions: ACSL contests can help students prepare for other programming competitions, such as the International Olympiad in Informatics (IOI) and the USA Computing Olympiad (USACO). The ACSL stresses its support network and resources, thus you are able to develop your skills as mentioned previously, and participate in other national and international competitions.

  3. College Applications: Participating in ACSL contests can demonstrate a student's interest and expertise in computer science on college applications. Colleges love admitting students with demonstrated interest in their field, rather than just saying they have an interest, thus participating in ACSL shows your personal drive and interest in the field of computer science.

  4. Networking: Students who participate in ACSL contests can meet other like-minded students who share their passion for computer science and technology, which allows you to share and develop ideas and shared knowledge, and have potential connections in the future with like-minded individuals. You also develop a close connection with your school advisor/mentor that leads your ACSL team, which could lead to a strong personal relationship for a future recommendation letter.

Overall, participating in the ACSL can be a great way for students to develop their programming skills, prepare for future competitions as you can start ACSL from a young age, and connect with other students who share their interests.

Who is Eligible to Participate in the American Computer Science League?

The American Computer Science League (ACSL) offers contests for students at various grade levels, so eligibility to participate depends on the specific contest. Here is a general overview:

  1. Elementary School Contests: The Elementary School Division is for students in grades 3-5.

  2. Middle School Contests: The Middle School Division is for students in grades 6-8.

  3. Junior Division Contests: The Junior Division is for students in grades 9-10.

  4. Senior Division Contests: The Senior Division is for students in grades 11-12.

Students who are enrolled in public, private, or home schools in the United States or abroad are eligible to participate in ACSL contests, so for high school students and below, you are likely welcome to participate!

Structure of the American Computer Science League

ACSL is a competition consisting of four regular-season contests. Students take all four tests. Each contest is available online for about 2 months. The online platform shuts down on the date listed in the Schedule page. This timeline likely varies year by year, but typically, Contest 1 will open in October, closes in January, Contest 2 opens in December, closes in March, Contest 3 opens in January, closes in April, and Contest 4 opens in March, and closes in May.

Based on the scores during the regular season, top students in all divisions will be invited to participate in an online Finals competition, which happens in late May.

The competition is separated by age into different categories.

  1. Senior Division - Best for high school students with programming experience, especially those taking AP Computer Science. Each contest consists of an online 30-minute, 5-question short answer test and an online programming problem to solve in 72 hours.

  2. Intermediate Division - Best for high school students with little or no programming experience and for advanced junior high students. Each contest consists of an online 30-minute, 5-question short answer test and an online programming problem to solve in 72 hours.

  3. Junior Division - Best for junior high and middle school students who are learning to program or who have coding experience. No student beyond grade 9 may compete in the Junior Division. Each contest consists of an online 30-minute, 5-question short answer test and an online programming problem to solve in 72 hours.

  4. Classroom Division - Open to students in all grades. Ideally suited for students taking AP Computer Science Principles, and other computer science classes without a major programming component. Each contest consists of an online 50-minute, 10-question short answer test. The problems are non-programming problems from the Junior, Intermediate, and Senior divisions.

  5. Elementary Division - Open to students in grades 3 - 6. Each contest consists of an online 30-minute, 5-question non-programming test, focused on a single category of content. A different category will be tested on each contest.

Tips to Win the American Computer Science League

Here are some tips to help you succeed in the competition:

  1. Practice, practice, practice: The best way to improve your programming skills is to practice as much as possible. Take advantage of the practice problems and resources provided by ACSL and work on solving as many problems as you can.

  2. Know the rules and format of the competition: Understanding the rules and format of the competition is crucial to your success. Make sure you are familiar with the competition guidelines, scoring system, and time limits.

  3. Pay attention to details: In programming, small mistakes can have big consequences. Be diligent in checking your code for errors and make sure you pay attention to details such as syntax, variable names, and formatting. Small errors can build up when the competition testing period is so short. Additionally, in a programming competition, efficiency is key. Make sure your code is optimized and avoid unnecessary loops and functions that could slow down your program.

  4. Collaborate with others: Working with others can be a great way to learn and improve your programming skills. Whether it is practicing with a group before the competition, or making sure that you’ve chosen a smart and dedicated team to work with while you compete.

  5. Stay calm under pressure: Programming competitions can be stressful, but it's important to stay calm and focused. Take deep breaths, stay positive, and remember that you've prepared for this moment.

By following these tips and practicing regularly, you can improve your chances of success in the ACSL and other programming competitions. Good luck!

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Ladder Internships is a selective program equipping students with virtual internship experiences at startups and nonprofits around the world! 

The startups range across a variety of industries, and each student can select which field they would most love to deep dive into. This is also a great opportunity for students to explore areas they think they might be interested in, and better understand professional career opportunities in those areas.

The startups are based all across the world, with the majority being in the United States, Asia and then Europe and the UK. 

The fields include technology, machine learning and AI, finance, environmental science and sustainability, business and marketing, healthcare and medicine, media and journalism and more.

You can explore all the options here on their application form. As part of their internship, each student will work on a real-world project that is of genuine need to the startup they are working with, and present their work at the end of their internship. In addition to working closely with their manager from the startup, each intern will also work with a Ladder Coach throughout their internship - the Ladder Coach serves as a second mentor and a sounding board, guiding you through the internship and helping you navigate the startup environment. 

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Application deadline: April 16 and May 14

Program dates: 8 weeks, June to August

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Additionally, you can also work on independent research in AI, through Veritas AI's Fellowship Program!

Veritas AI focuses on providing high school students who are passionate about the field of AI a suitable environment to explore their interests. The programs include collaborative learning, project development, and 1-on-1 mentorship. 

These programs are designed and run by Harvard graduate students and alumni and you can expect a great, fulfilling educational experience. Students are expected to have a basic understanding of Python or are recommended to complete the AI scholars program before pursuing the fellowship. 

The AI Fellowship program will have students pursue their own independent AI research project. Students work on their own individual research projects over a period of 12-15 weeks and can opt to combine AI with any other field of interest. In the past, students have worked on research papers in the field of AI & medicine, AI & finance, AI & environmental science, AI & education, and more! You can find examples of previous projects here

Location: Virtual


  • $1,790 for the 10-week AI Scholars program

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  • $4,700 for both

  • Need-based financial aid is available. You can apply here

Application deadline: On a rolling basis. Applications for fall cohort have closed September 3, 2023. 

Program dates: Various according to the cohort

Program selectivity: Moderately selective

Eligibility: Ambitious high school students located anywhere in the world. AI Fellowship applicants should either have completed the AI Scholars program or exhibit past experience with AI concepts or Python.

Application Requirements: Online application form, answers to a few questions pertaining to the students background & coding experience, math courses, and areas of interest. 

One more option - the Lumiere Research Scholar Program

If you’re looking for a mentor to participate in a coding competition like the American Computer Science League, or want another opportunity to build your own independent project and research paper, then consider applying to the Lumiere Research Scholar Program. Last year over 2100 students applied for about 500 spots in the program. You can find the application form here.

Aaron Zheng is a sophomore at Harvard University, studying Bioengineering. He is passionate about biotechnology, business development, and aiding students get to college, regardless of background. In his spare time, he looks to read, journal, and explore the world.

Image source: ASCL logo



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