Interactive Primer
Interactive Primer is a free, open-source collection of web lessons in mathematics, computer science, and physics.
What Interactive Primer is
Interactive Primer is a free, open-source collection of web lessons in mathematics, computer science, and physics. Each concept has a dedicated page, and courses link related topics into guided learning paths. Lessons combine animations, interactive diagrams, and randomized quizzes. A Getting Started quiz helps locate what a learner already knows in school mathematics, physics, or computer science, while a dashboard shows mastery, streaks, new material ready to learn, and reviews due. The school library ranges from early counting through A-level and beyond, with no sign-up or installation required. Lessons map to UK Key Stages, GCSE and A-level, US Common Core and AP, Australian, Canadian, and South African syllabuses, and IB programmes. Progress remains in the learner’s browser unless they choose to sync it. The lessons use CC BY-SA 4.0 and the code uses AGPL-3.0. The site aims for WCAG 2.1 Level AA but says it is only partially conformant; its graph explorer is not yet fully operable by keyboard or screen reader.
Good
- Guided courses connect related concepts.
- Lessons use diagrams, animations, and quizzes.
- No sign-up or installation is required.
- Progress stays in the browser unless synced.
Watch out
- The site describes accessibility as partially conformant.
- The graph explorer lacks full keyboard and screen-reader operation.
Who it suits
It suits learners and schools seeking browser-based lessons in mathematics, computer science, or physics. Its curriculum mappings may help learners following the listed regional programmes.
Verdict
Interactive Primer offers a broad set of structured lessons and practice without requiring an account or installation. Learners who rely on keyboard or screen-reader access should note the stated limitation in the graph explorer.
Plans and prices
From Interactive Primer's own pricing page, checked 12 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free | Free | No sign-up · no subscriptions · no ads |
The facts
Each one read from Interactive Primer's own pages, with the date it was checked.
What it does
- Accessibility
- The site aims to meet WCAG 2.1 Level AA and says it is partially conformant; the graph explorer is not yet fully keyboard- or screen-reader-operable.checked 12 Oct 2026
- Adaptive learning
- Yeschecked 22 Sep 2026
- Curricula
- The lessons are mapped to UK Key Stages, GCSE and A-level; US Common Core and AP; Australian, Canadian, and South African syllabuses; and IB programmes.checked 12 Oct 2026
- For schools
- The school library covers mathematics, physics, and computer science from early counting through A-level and beyond, with no sign-up or installation required.checked 12 Oct 2026
- Gamified practice
- Yeschecked 22 Sep 2026
- Guided lessons
- Yeschecked 22 Sep 2026
- Interactive content
- Lessons use animations, interactive diagrams, and randomized quizzes.checked 12 Oct 2026
- Lessons
- Each concept is taught on its own page, and courses provide guided paths through related concepts.checked 12 Oct 2026
- Licenses
- The lessons use CC BY-SA 4.0 and the code uses AGPL-3.0.checked 12 Oct 2026
- Offline access
- Yeschecked 22 Sep 2026
- Placement
- A Getting Started quiz identifies a learner’s knowledge frontier in school mathematics, physics, or computer science.checked 12 Oct 2026
- Privacy
- Student progress stays in the learner’s browser unless they choose to sync it.checked 12 Oct 2026
- Progress tracking
- The progress dashboard shows mastery, streaks, what is ready to learn, and what is due for review.checked 12 Oct 2026
- Security and compliance
- The opened maker pages provide no stated security certification or compliance claim.checked 12 Oct 2026
- Support
- Users can report page-specific feedback through the site menu or contact the project through GitHub Discussions.checked 12 Oct 2026
- Themes and language
- The site offers light, dark, and fun themes, and lets users switch the language from the menu.checked 12 Oct 2026
- What it is
- Interactive Primer is a free, open-source collection of smart web pages teaching mathematics, computer science, and physics.checked 12 Oct 2026
Money
- Free plan
- Yeschecked 22 Sep 2026
Where it runs
- Supported platforms
- webchecked 22 Sep 2026
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