Compulsory & Elective Courses Explained

Everything You Need to Know About Choosing Courses for Your Ontario Secondary School Diploma

Quick Answer

What Are Compulsory and Elective Courses?

To earn an Ontario Secondary School Diploma (OSSD), students beginning Grade 9 in 2024 and later must complete:

• 17 compulsory credits (required subjects)

• 13 elective (optional) credits chosen according to their interests, university prerequisites, and career goals.

Together, these 30 credits satisfy the academic credit requirements needed to graduate with an OSSD.

Key Takeaways

Every OSSD requires 30 total credits.

✔ 17 credits are compulsory.

✔ 13 credits are electives.

✔ Elective courses should support university and career goals.

✔ Some university programs require specific Grade 12 courses.

✔ Academic planning helps students avoid taking unnecessary courses.

Understanding Ontario Course Credits

Earning an Ontario Secondary School Diploma (OSSD) begins with understanding how Ontario’s high school credit system works.

A credit is awarded when a student successfully completes the expectations of a course approved by the Ontario Ministry of Education. Credits are the building blocks of your high school education and are used to measure your progress toward graduation.

Most full-credit courses are designed to provide approximately 110 hours of instruction, while some courses, such as Civics and Citizenship Studies, are worth 0.5 credit.

Students earn credits across Grades 9–12 by completing courses in a variety of subject areas, including English, mathematics, science, Canadian studies, languages, business, technology, the arts, and more.

To graduate with an Ontario Secondary School Diploma, students beginning Grade 9 in September 2024 or later must successfully complete:

30 total credits
17 compulsory credits in required subject areas
13 elective credits chosen according to their interests and future goals

These credits work together to ensure students receive both a strong academic foundation and the flexibility to explore subjects that prepare them for university, college, apprenticeships, or future careers.

What Are Compulsory Courses?

Compulsory courses are the required subjects that every Ontario high school student must successfully complete to earn an Ontario Secondary School Diploma.

These courses are designed by the Ontario Ministry of Education to ensure all graduates develop essential knowledge and skills in core academic areas such as English, mathematics, science, Canadian studies, physical education, French as a Second Language, and career education.

Rather than allowing students to choose every course freely, compulsory credits create a common educational foundation that prepares students for further education, employment, and everyday life.

Students who began Grade 9 in September 2024 or later must earn 17 compulsory credits as part of the 30 creditsrequired for graduation.

Although these courses are mandatory, students still have opportunities to choose specific course pathways—such as Academic, Applied (where applicable), Open, College, University, University/College, Workplace, or Mixed preparation courses in the appropriate grades—and later complement them with elective courses that align with their interests and post-secondary goals.

At Ontario International School, our Academic Advising Team helps students understand which compulsory courses they need, how those courses fit into their graduation plan, and which electives best support their intended university or career pathway.

The 17 Compulsory Credits Required for an OSSD

The Ontario Ministry of Education requires every student working toward an Ontario Secondary School Diploma (OSSD) to complete 17 compulsory credits. These courses provide a strong academic foundation and ensure that every graduate develops essential knowledge, practical skills, and the preparation needed for post-secondary education, employment, and lifelong learning.

The compulsory credits span a variety of subject areas, including language, mathematics, science, Canadian studies, health and physical education, the arts, French as a Second Language, and career education. Together, they help students build critical thinking, communication, problem-solving, and digital literacy skills that are valuable in university, college, apprenticeships, and the workplace.

The table below outlines the compulsory credit requirements for students beginning Grade 9 in September 2024 or later.

The 17 Compulsory Credits at a Glance

Subject Area	Credits Required
English	4
Mathematics	3
Science	2
Canadian History	1
Canadian Geography	1
The Arts	1
Health and Physical Education	1
French as a Second Language	1
Career Studies	1
Civics and Citizenship Studies	0.5
Computer Studies, Technological Education, or Cooperative Education	1
Additional Compulsory Credit Group 1	1
Additional Compulsory Credit Group 2	1
Additional Compulsory Credit Group 3	0.5
Total	17 Credits

Note: The three Additional Compulsory Credit Groups allow students to meet graduation requirements through approved courses in designated subject areas. The specific course chosen depends on the student’s academic pathway and must comply with Ontario Ministry of Education requirements. Your Academic Advisor can help you determine which courses best fit your graduation and university plans.

Why Are These Courses Required?

Each compulsory subject contributes to a well-rounded education by developing a different set of knowledge and skills.

English strengthens reading, writing, communication, and critical thinking.
Mathematics develops logical reasoning, problem-solving, and analytical skills.
Science builds scientific literacy and inquiry skills.
Canadian History and Geography help students understand Canada’s past, society, environment, and civic responsibilities.
Health and Physical Education promotes lifelong physical and mental well-being.
The Arts encourage creativity, collaboration, and self-expression.
French as a Second Language develops communication skills in Canada’s second official language.
Career Studies and Civics and Citizenship Studies prepare students for career planning, financial literacy, civic engagement, and responsible citizenship.

Together, these required courses ensure that every Ontario graduate receives a balanced education while developing the competencies needed for success beyond high school.

Can My Previous Studies Count Toward These Requirements?

If you’ve previously studied at another Ontario school, another Canadian province, or an international school, you may not need to complete all 17 compulsory credits from the beginning.

Depending on your educational background, some previously completed courses may be recognized through a transcript assessment (often referred to as PLAR or credit recognition, where applicable). This process helps determine which graduation requirements you have already met and which courses you still need to complete.

At Ontario International School, our Academic Advising Team offers a Free Transcript Assessment to evaluate your previous studies and create a personalized graduation plan based on your academic history.

Related Resources:
What Is PLAR? A Complete Guide for OSSD Students
Free Academic Assessment

What Are Elective Courses?

After completing the 17 compulsory credits, students earn the remaining 13 credits through elective courses (also known as optional credits).

Elective courses allow students to personalize their education by choosing subjects that match their interests, strengths, post-secondary plans, and career aspirations. While these credits are called “elective,” they play a significant role in preparing students for life after high school.

Unlike compulsory courses, which are required for every student, elective courses provide flexibility. Students can explore new areas of interest, deepen their knowledge in specific subjects, or build the academic background needed for competitive university programs.

Whether you’re interested in engineering, business, health sciences, computer science, the arts, or skilled trades, your elective course selections can help you develop the knowledge and skills required for your chosen pathway.

Why Elective Courses Matter

Choosing elective courses is about much more than filling graduation requirements. The decisions you make today can influence your university admission opportunities, career options, and overall educational experience.

Well-planned electives can help you:

Meet university or college admission prerequisites.
Explore potential career interests before graduation.
Strengthen skills in subjects you enjoy.
Build a more competitive academic profile.
Discover new talents and future career pathways.

Students who choose electives strategically often have greater flexibility when applying to post-secondary programs and may feel more confident about their future academic goals.

Examples of Popular Elective Pathways

Although every student’s plan is unique, elective courses often reflect future educational and career interests.

Engineering and Computer Science

Students interested in engineering, software development, or technology often choose electives such as:

Computer Science
Computer Engineering Technology
Physics
Advanced Mathematics
Technological Education

Business and Commerce

Students planning to study business frequently select electives including:

Accounting
Business Leadership
Entrepreneurship
Marketing
Economics

Health Sciences and Medicine

Students preparing for programs such as nursing, medicine, pharmacy, or life sciences commonly focus on:

Biology
Chemistry
Physics
Advanced Mathematics
Health-related courses where available

Arts and Creative Industries

Students pursuing creative careers may choose electives such as:

Visual Arts
Media Arts
Drama
Music
Communications Technology

Skilled Trades and Technology

Students interested in apprenticeship pathways or technical careers often benefit from electives in:

Construction Technology
Manufacturing Technology
Hospitality and Tourism
Transportation Technology
Cooperative Education

How to Choose the Right Elective Courses

There is no single set of “best” elective courses. The right choices depend on your individual goals.

Before selecting your electives, ask yourself:

Which university or college programs am I considering?
What subjects do I enjoy most?
Which courses are required for my future program?
What skills would I like to develop?
Do my electives support my long-term career goals?

Planning ahead helps you avoid taking unnecessary courses and ensures your electives contribute to both your graduation requirements and your future aspirations.

At Ontario International School, our Academic Advising Team works one-on-one with students to recommend elective courses that align with their interests, graduation requirements, and post-secondary goals.

Related Resources:
University Prerequisite by Program

How University Prerequisites Affect Course Selection

Choosing your courses isn’t just about meeting the requirements to earn an Ontario Secondary School Diploma (OSSD). If you’re planning to attend university, your course selection can also determine which programs you’re eligible to apply for.

Most Canadian universities require applicants to complete specific Grade 12 courses before they can be considered for admission. These are known as prerequisite courses.

For example, while two students may both earn an OSSD, one may qualify for an Engineering program and the other may not—simply because they selected different Grade 12 courses.

Planning your course selection early helps ensure you graduate with both your OSSD and the academic prerequisites required for your intended post-secondary program.

What Are University Prerequisite Courses?

University prerequisite courses are specific high school courses that must be completed before applying to certain university programs.

These prerequisites vary depending on the institution and the program of study. Admission requirements are established by each university, so students should always review the latest information directly from the universities they plan to apply to.

Some programs require only a few prerequisite courses, while others expect students to complete several advanced Grade 12 subjects.

Examples of Common University Prerequisites

The table below highlights examples of common prerequisite courses. Requirements vary by institution and program and should always be verified before applying.

University Program	Common Grade 12 Prerequisites*
Engineering	Advanced Functions (MHF4U), Calculus and Vectors (MCV4U), Chemistry (SCH4U), Physics (SPH4U), English (ENG4U)
Computer Science	Advanced Functions (MHF4U), Calculus and Vectors (MCV4U), English (ENG4U); some universities also require or recommend Physics (SPH4U)
Health Sciences	English (ENG4U), Biology (SBI4U), Chemistry (SCH4U); some programs also require Advanced Functions (MHF4U)
Nursing	English (ENG4U), Biology (SBI4U), Chemistry (SCH4U), one senior Mathematics course
Business	English (ENG4U), Advanced Functions (MHF4U); some programs also recommend Calculus and Vectors (MCV4U)
Arts & Humanities	English (ENG4U); additional prerequisites vary by program

*Examples only. Admission requirements differ by university and program.

Why Planning Ahead Matters

Waiting until Grade 12 to think about university requirements can limit your options.

Some Grade 12 courses require students to complete specific Grade 11 prerequisite courses first. If those earlier courses are missed, students may need additional time to complete the necessary sequence before applying to university.

Planning your courses from Grade 9 onward helps you:

Stay on track for graduation.
Meet university admission prerequisites.
Keep multiple post-secondary options open.
Reduce the need for additional upgrading courses.
Feel more confident about your academic pathway.

A well-planned course sequence gives you greater flexibility when it’s time to apply to university.

How Ontario International School Helps Students Plan Their Courses

Every student’s educational journey is different. Some students begin in Grade 9 at Ontario International School, while others transfer from another Ontario school, another Canadian province, or an international education system.

Our Academic Advising Team works closely with each student to create a personalized academic plan based on their previous studies, graduation requirements, and future goals.

We help students:

Review previous transcripts and eligible transfer credits.
Select appropriate compulsory and elective courses.
Identify university prerequisite courses.
Develop a multi-year academic plan.
Stay on track toward graduation and university admission.

Whether you’re still exploring career options or already know the university program you want to pursue, personalized academic planning can help you make informed course selections with confidence.

Common Course Selection Mistakes (and How to Avoid Them)

Choosing your high school courses is one of the most important decisions you’ll make during your Ontario Secondary School Diploma (OSSD) journey. While every student’s pathway is unique, there are several common mistakes that can delay graduation, limit university options, or result in unnecessary coursework.

Understanding these challenges early can help you make informed decisions and build a course plan that supports both your graduation requirements and your long-term goals.

Waiting Too Long to Plan

Many students don’t begin thinking about graduation requirements or university prerequisites until Grade 12. By then, they may discover that they are missing prerequisite courses or need to complete additional credits before applying to their preferred program.

How to avoid it: Start planning your course pathway as early as possible. Reviewing your academic goals in Grades 9 or 10 gives you greater flexibility and helps you stay on track throughout high school.

Choosing Courses Without Considering University Requirements

Selecting courses based only on personal interest may limit your eligibility for certain university programs. Many competitive programs require specific Grade 12 university preparation courses that must be completed before applying.

How to avoid it: Research the admission requirements for programs you’re interested in and choose courses that satisfy both your graduation requirements and university prerequisites.

Related Resource:
University Prerequisites by Program

Assuming Previous Credits Automatically Count

Students transferring from another Ontario school, another Canadian province, or another country sometimes assume that all previously completed courses will automatically satisfy Ontario graduation requirements. In reality, every student’s educational background must be evaluated individually.

How to avoid it: Request a transcript assessment before selecting new courses. This helps identify eligible transfer credits and ensures you understand exactly what remains to graduate.

Related Resource:
What Is PLAR? A Complete Guide for OSSD Students

Taking Courses Without a Long-Term Plan

It’s common for students to choose courses one semester at a time without considering how those decisions affect future opportunities. This approach can result in unnecessary courses or missed prerequisites.

How to avoid it: Develop a multi-year academic plan that considers your graduation requirements, university goals, and personal interests together.

Not Asking for Academic Advice

Ontario’s graduation requirements, course codes, prerequisite chains, and university admission requirements can be confusing, especially for students and families who are new to the Ontario education system.

Trying to plan everything independently can lead to avoidable mistakes.

How to avoid it: Work with an Academic Advisor who can review your educational background, explain your graduation requirements, recommend appropriate courses, and help you stay on track toward your goals.

At Ontario International School, every student receives personalized academic guidance designed to support informed course selection and long-term success.

A Personalized Course Plan Makes the Difference

No two students have exactly the same educational journey. Some students begin Grade 9 at Ontario International School, while others transfer from another Ontario school, another province, or an international education system.

That’s why a personalized course plan is one of the most valuable tools for achieving academic success.

Our Academic Advising Team helps students:

Understand their graduation requirements.
Review previous studies and transfer credits.
Choose appropriate compulsory and elective courses.
Plan for university admission requirements.
Stay on track toward earning an Ontario Secondary School Diploma.

With the right guidance, students can avoid common planning mistakes and move forward with confidence, knowing their course selections support both graduation and future educational goals.

Why Students choose Ontario International School?

Choosing the right courses is about more than meeting graduation requirements—it’s about creating a pathway toward future success.

At Ontario International School, we combine Ontario’s curriculum with personalized academic guidance to help students make confident decisions throughout their high school journey.

Whether you’re beginning Grade 9, transferring from another school, upgrading prerequisite courses, or preparing for university admission, our Academic Advising Team works with you to develop a course plan that aligns with your academic goals.

Students choose Ontario International School because we provide:

✔ Personalized Academic Advising
Receive one-on-one guidance to help you understand graduation requirements, choose the right courses, and plan your pathway to post-secondary education.

✔ Flexible Online Learning
Study from anywhere with a schedule that fits your lifestyle while completing Ontario curriculum courses.

✔ Free Transcript Assessment
If you’re transferring from another school or another country, we’ll review your previous studies to determine eligible transfer credits and identify the courses you still need.

✔ University Pathway Planning
We help students select Grade 11 and Grade 12 courses that align with university prerequisites and long-term career goals.

✔ Rolling Enrollment
Start your studies throughout the year instead of waiting for a traditional semester intake.

✔ Comprehensive Grade 9–12 Course Selection
Choose from a wide range of Ontario curriculum courses designed to support graduation and university preparation.

✔ Support for Domestic and International Students
Whether you live in Ontario, another Canadian province, or abroad, our team provides personalized guidance tailored to your educational background and future plans.

At Ontario International School, our goal is to help every student move beyond simply earning credits. We help students build a personalized academic pathway that supports graduation, university admission, and long-term success.

Ready to Plan Your Ontario High School Courses?

Every successful academic journey begins with the right course plan.
Whether you're choosing your first Ontario high school courses, transferring from another school, or preparing for university, our Academic Advising Team is here to help.

During your Free Academic Assessment, we'll help you:

✓ Review your previous academic records

✓ Explain your graduation requirements and credit pathway

✓ Recommend the right compulsory and elective courses

✓ Identify the university prerequisite courses you need

✓ Create a personalized academic pathway toward graduation and university success

Get a Free Academic Assessment Speak with an Academic Advisor

Frequently Asked Questions (FAQ)

What is the difference between compulsory and elective courses?

Compulsory courses are the required subjects every student must complete to earn an Ontario Secondary School Diploma (OSSD). Elective courses, also called optional courses, allow students to personalize their education based on their interests, university prerequisites, and career goals. Together, compulsory and elective courses make up the 30 creditsrequired for graduation.

How many compulsory and elective credits do I need?

Students beginning Grade 9 in September 2024 or later must complete:

17 compulsory credits
13 elective credits

Together, these 30 credits satisfy the academic credit requirement for earning an Ontario Secondary School Diploma. Additional graduation requirements, such as literacy, community involvement, online learning, and financial literacy (for applicable cohorts), must also be completed.

Related Resource: OSSD Graduation Requirements Explained

Can I choose any elective courses I want?

You have flexibility when selecting elective courses, but your choices should support both your graduation requirements and your future goals. Some university and college programs require specific Grade 11 and Grade 12 courses, so it’s important to plan your electives carefully.

How do I know which courses I need for university?

Every university and program has its own admission requirements. Many programs require specific Grade 12 university preparation courses, particularly in subjects such as English, mathematics, biology, chemistry, and physics.

Our Academic Advising Team helps students identify the courses required for their intended university program and create a personalized academic plan.

Related Resource: University Prerequisites by Program

Can I change my course selections later?

In many cases, yes. However, changing courses may affect your graduation timeline or university eligibility if prerequisite courses are involved.

Before making changes, it’s a good idea to speak with an Academic Advisor to understand how your decisions may affect your academic pathway.

Can transfer credits count toward compulsory or elective courses?

They may. Students transferring from another Ontario school, another Canadian province, or another country may receive eligible transfer credits after their previous studies have been evaluated.

A transcript assessment helps determine which graduation requirements have already been met and which courses remain.

Related Resource: What Is PLAR? A Complete Guide for OSSD Students

What if I don't know what I want to study after high school?

That’s completely normal. Many students begin high school without a clear career goal.

In this situation, it’s often helpful to choose courses that keep multiple post-secondary pathways open while exploring your interests over time. Academic Advisors can help you build a flexible course plan that allows you to make informed decisions as your goals become clearer.

What if I choose the wrong courses?

Choosing the wrong courses doesn’t necessarily prevent you from reaching your goals, but it may require additional courses or adjustments to your academic plan.

Planning ahead and seeking academic advice early can help you avoid unnecessary delays and ensure you’re taking courses that support your future education.

Can Ontario International School help me choose my courses?

Yes. Ontario International School provides personalized academic advising to help students:

Understand graduation requirements.
Review previous studies and transfer credits.
Select appropriate compulsory and elective courses.
Plan for university admission.
Build a personalized pathway toward earning an Ontario Secondary School Diploma.

How do I get started?

Getting started is simple.

Begin by requesting a Free Academic Assessment. Our Academic Advising Team will review your educational background, discuss your goals, explain your graduation requirements, and recommend the courses that best support your pathway toward graduation and post-secondary success.

Related Resources

Online OSSD for International Students

Learn how international students can earn an Ontario Secondary School Diploma online and prepare for university from anywhere in the world.

OSSD Graduation Requirements

Understand the credits, literacy requirement, and community involvement hours needed to earn an Ontario Secondary School Diploma.

What Is PLAR? A Complete Guide for OSSD Students

Discover how Prior Learning Assessment and Recognition (PLAR) may help eligible students receive recognition for previous education and reduce the number of courses needed to graduate.

Applying to Ontario Universities Through OUAC

Learn how OSSD students apply to Ontario universities through the Ontario Universities' Application Centre (OUAC).

How to Research Universities Using OUInfo

Discover how to compare Ontario university programs, admission requirements, and prerequisites using OUInfo.

University Prerequisites

Find the Grade 11 and Grade 12 Ontario courses commonly required for programs such as Engineering, Business, Computer Science, Health Sciences, and more.

References

To ensure the information in this guide is accurate and up to date, we recommend consulting the following official resources: