If you are a high school student interested in exploring new subjects or strengthening academic skills, taking a free online course can be an accessible, low-pressure way to get started. Free online courses are college-level or advanced enrichment and skill-building classes that you can access without paying tuition. Many of these courses are offered by universities or education-focused nonprofits. These courses span a wide range of fields, such as STEM, finance, architecture, philosophy, data science, and the arts. They allow you to experiment with different academic paths while building practical skills like coding, scientific writing, quantitative reasoning, and research skills.
Benefits of online courses
Some courses may also include structured projects, technical exercises, or certificates of completion that can support future college applications by demonstrating initiative and academic curiosity. The work you produce here can still strengthen your resume or give you specific experiences to reference in college essays.
In this blog, we have put together 15 free online courses for high school students. We have prioritized options that offer structured learning, skill development, and a flexible way to explore potential college majors or career interests. You can also check out our blog on online summer research programs for high school students.
15 Free Online Courses for High School Students
1. Virtual NSLI-Y
Location: Online
Cost: Free
Acceptance rate/cohort size: Overall figures not specified; 10 students/classroom
Dates: September – November (exact dates may vary based on class schedule)
Application deadline: May – June (exact dates TBD)
Eligibility: U.S. high school students, ages 15–18, who are beginners/novice-level learners in the selected target language
Virtual NSLI-Y is a 10-week online language program where you will study beginner-level Arabic, Mandarin, or Russian in small virtual classes led by experienced instructors. You will attend live sessions twice a week, focusing on conversation practice, short projects, and structured cultural learning tied to the regions where the specific language is spoken. The curriculum incorporates activities such as skits, role-plays, video entries, guest speaker sessions, and virtual cultural tours to help you develop basic communication skills and intercultural awareness. Homework and assessments, as well as optional community-building events for those who want extra practice, are part of the experience.
2. CDC Museum Public Health Academy (CDCM PHA) Online Summer Course
Location: Online
Cost: Free
Acceptance rate/cohort size: ~75 spots (tentative; subject to change)
Dates: June 9 – 13 (tentative; subject to change)
Application deadline: March 7 (tentative; subject to change)
Eligibility: Rising high school juniors or seniors who are at least 16 years old
As a CDC PHA Summer Course participant, you will study how public health problems are investigated and addressed through a mix of independent lessons and daily live sessions led by CDC educators and subject matter experts. You will explore concepts in epidemiology, disease surveillance, environmental health, chronic diseases, and global health while practicing skills in data interpretation, case study analysis, and scientific communication. The course involves both asynchronous and synchronous components, including videos, knowledge self-checks, readings, live lectures, discussions, case studies, and quizzes. This course is designed to be a focused way to understand how CDC approaches population health and real-world public health problems.
3. HarvardX: CS50’s Introduction to Computer Science
Location: Online via edX
Cost: Free ($219 for a verified certificate)
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced; takes around 12 weeks to complete
Application deadline: Open enrollment
Eligibility: Open to all, including high school students
HarvardX: CS50’s Introduction to Computer Science is a self-paced course where you will learn the fundamentals of computer science by working through problem sets grounded in topics like biology, cryptography, and finance. You will study core concepts such as algorithms, abstraction, data structures, web development, and basic software engineering, while becoming familiar with programming languages such as C, Python, SQL, JavaScript, HTML, and CSS. The course focuses on helping you learn how to think algorithmically and approach problems with efficiency and structure. If you complete all required assignments and a final project, you will be eligible to earn a certificate.
4. Stanford Program for Inspiring the Next Generation of Women in Physics (SPINWIP)
Location: Online
Cost: Free
Acceptance rate/cohort size: Not specified
Dates: July 7 – 25 (tentative; subject to change)
Application deadline: May 1 (tentative; subject to change)
Eligibility: Current high school freshmen, sophomores, and juniors
SPINWIP is a free, three-week virtual course where you will explore key areas of modern physics through lectures, coding sessions, and small group discussions. You will study topics such as astrophysics, quantum physics, cosmology, and quantum computing while learning to write basic Python programs and apply them to physics-based problems. The program blends faculty-led instruction with peer-supported group work, giving you regular opportunities to troubleshoot concepts, analyze data using predictive models, and practice scientific reasoning. You will also engage in college and career workshops and access the mentorship of Stanford undergraduates and researchers while focusing on building technical fluency, computational skills, and a clearer understanding of physics career pathways.
5. Stanford University’s Understanding Einstein: The Special Theory of Relativity Course
Location: Online via Coursera
Cost: Free to audit
Acceptance rate/cohort size: Not specified
Dates: Self-paced; approximately two months (10 hours/week)
Application deadline: None
Eligibility: Open to all learners; skills in algebra and introductory calculus recommended
This free online course offers an introduction to Albert Einstein’s special theory of relativity and its paradoxes. You will dive into the meaning of the theory as well as concepts like relativity of simultaneity, Lorentz factor, time dilation, and the problems and reception of the theory of relativity. You will learn through eight modules that include reading material, videos, and assignments. Quizzes are also part of the experience, allowing you to revisit what you learn and track your progress.
6. Google’s Machine Learning Crash Course
Location: Online
Cost: Free
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced
Application deadline: None; open enrollment
Eligibility: Open to everyone, including high school students; recommended coursework prerequisites are Algebra, Linear Algebra, Trigonometry, Statistics, and optionally Calculus.
Google’s Machine Learning Crash Course is a self-paced online program that introduces you to core concepts and workflows used in modern AI. Through modules developed by Google researchers, you will work through topics such as regression, classification, neural networks, embeddings, and large language models. You will also become familiar with ML datasets, best practices for productionization, and fairness considerations when using ML models. The course integrates theory with hands-on practice, offering you more than 100 coding exercises and visualizations to apply all concepts as you learn them. You will finish the program with a certificate of completion.
7. MIT OpenCourseWare’s Introduction to Architecture & Environmental Design
Location: Online
Cost: Free
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced; available year-round
Application deadline: None; open enrollment
Eligibility: Open to everyone, including high school students
MIT OpenCourseWare’s Introduction to Architecture & Environmental Design course provides a structured entry point into how architects approach topics such as urbanism and environmental design. Through lectures and design exercises, you will build skills in spatial representation, design methodologies, and the design process. Assignments will guide you in examining form, structure, and tectonic movement while building your analytical skills. The course also focuses on architecture and urbanism within the broader artistic and scientific contexts, helping you understand how design decisions shape the environments we live in.
8. Rice University’s Physics 101: Energy and Momentum Course
Location: Online via Coursera
Cost: Free to audit
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced; a commitment of two weeks (10 hours/week)
Application deadline: None
Eligibility: Open to all; familiarity with algebra and introductory calculus concepts is recommended.
This course focuses on the mathematical framework behind conservation of energy and momentum, focusing on how these concepts apply to the motions of objects. You will work on problems covering work–energy link, statics, translational momentum, collisions, and elasticity using algebra and basic calculus. The modules come with lecture videos, quizzes, and homework that mirror college-level introductory physics courses. You will also work with graphical analysis tools as a participant.
9. Meta’s Programming in Python Course
Location: Online via Coursera
Cost: Free
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced; requires a commitment of around 50 hours
Application deadline: None; open enrollment
Eligibility: Open to all, including high school students
Meta’s Programming in Python course offers a structured introduction to core programming concepts using Python. You will learn how to write and debug code, work with variables and data types, use control flows and loops, and build functions and data structures. The course also covers object-oriented programming, basic error handling, and writing simple unit tests so you can practice test-driven development. This course is designed for beginners interested in areas like back-end development or database engineering, and you only need basic computer skills to get started.
10. HarvardX: Justice Course
Location: Online via edX
Cost: Free (or $209 for certificate)
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced; takes around 12 weeks to complete
Application deadline: None; open enrollment
Eligibility: Open to everyone, including high school students; no prior experience required
HarvardX: Justice offers an introductory look at moral and political philosophy through case studies, discussions of contemporary issues, and classical texts. As a participant, you will examine topics like equality, human rights, income distribution, affirmative action, and the role of markets, using arguments from thinkers such as Aristotle, Kant, Mill, and Rawls. The course will also help you learn how to analyze claims, evaluate reasoning, and question your own assumptions about social and criminal justice. If you are interested in how philosophical ideas show up in real policy debates, this online course might be worth checking out.
11. ColumbiaX: Introduction to Corporate Finance
Location: Online
Cost: Free or $225 for certificate
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced; takes around four weeks to complete
Application deadline: None; open enrollment
Eligibility: Open to everyone, including high school students
This self-paced program covers the core ideas in corporate finance, focusing on how firms evaluate investments and manage financial decisions, through modules led by a Columbia University instructor. This course is designed for those who want a clear, analytical introduction to financial decision-making and basic valuation methods. As a participant, you will explore concepts such as the time value of money, cost of capital, and capital budgeting, and learn how to use Excel to value stocks and bonds, calculate NPV (Net present value), and determine IRR (Internal rate of return). The curriculum also includes projects, where you will analyze company proposals, estimate returns, and compute bond yields.
12. UChicago Medicine’s Summer Healthcare Experience in Oncology
Location: Online
Stipend: $500
Acceptance rate/cohort size: 20 spots/year
Dates: July 13 – 25
Application deadline: March 2
Eligibility: High school students from Cook, Lake, Will, or DuPage counties in Illinois or Lake County in Indiana
UChicago Medicine’s Summer Healthcare Experience in Oncology is a two-week virtual program where you will work with peers across multiple universities to study cancer from both a research and patient-care perspective. You will collaborate on a genetics-based research project, analyze a patient case study, and attend daily lectures and panels led by faculty and professionals in the cancer field. The program also includes workshops that can help you build basic research skills and understand different biomedical career paths. You will receive a home lab kit for hands-on work and a taxable $500 stipend.
13. Stanford’s Code in Place Course
Location: Virtual
Cost: None
Acceptance rate/cohort size: Not specified
Dates: Starts in April and runs for about six weeks
Application deadline: Spring; date TBA
Eligibility: Open to all
Stanford University offers learners of all ages free access to content from its flagship CS106A course, which is a structured introduction to programming using Python, through the Code in Place course. Here, you will explore core concepts like loops, control flow, conditionals, and console programs with graphics, dictionaries, lists, and variables through sessions led by teachers, university students, programmers, or other instructors. Additionally, you will work on projects and build games to apply concepts that you learn during the course. Once a week, you will attend a virtual session connecting with 10 other students.
14. Girls Who Code Pathways
Location: Online
Cost: Free
Acceptance rate/cohort size: Not specified
Dates: Multiple six to seven-week sessions throughout the year
Application deadline: Varies by session
Eligibility: High school girls and non-binary students aged 14–18
Girls Who Code Pathways is a six–week, self-paced program for high school students interested in building foundational skills in computer science. You can choose from tracks such as data science and AI, cybersecurity, or web development, and learn through structured projects that introduce you to tools like Python, HTML, CSS, and JavaScript. In the process, you will build core technical skills such as problem-solving, basic data analysis, and introductory software development. The program also offers access to a virtual Discord community where you can ask questions, share work, and connect with like-minded peers. Additionally, you will be able to attend optional events where you can hear from tech professionals and explore different career paths in the field.
15. University of Michigan’s Web Design for Everybody: Basics of Web Development & Coding Specialization
Location: Online via Coursera
Cost: Free; optional fee for certificate of completion
Acceptance rate/cohort size: Open enrollment
Dates: Self-paced; commitment of ~80 hours
Application deadline: None; open enrollment
Eligibility: Open to all
University of Michigan’s Web Design for Everybody is designed to help you develop skills in website development and user interface design. You will learn how to work with JavaScript, HTML, and CSS to create websites for computers, phones, and tablets. The specialization is split into courses, each with a dedicated focus area, like HTML5, CSS3, coding skills for website-user interactivity, and advanced styling and responsive design. The course will also cover how to modify your site’s code for accessibility, including modifications for individuals with visual, auditory, or physical impairments. You will complete the course with a web portfolio, which you can continue to work on and use in college applications.
One more option – Horizon Academic Research Program
If you’re looking for a competitive mentored research program in subjects like data science, machine learning, political theory, biology, and chemistry, consider applying to Horizon’s Research Seminars and Labs! This is a selective virtual research program that lets you engage in advanced research and develop a research paper on a subject of your choosing. Horizon has worked with 1000+ high school students so far and offers 600+ research specializations for you to choose from. You can find the application link here!
Image Source – University of Chicago logo