CK-12 FlexBook 2.0 vs Opiq
CK-12 FlexBook 2.0
ck12.org
Opiq
opiq.eeSide by side
| Figure | CK-12 FlexBook 2.0 | Opiq |
|---|---|---|
| Price from | Free | €1/mo |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| iOS | Yes | Yes |
| Android | Yes | Yes |
| Plans published | 2 | 5 |
| Spec score · Digital Textbook Platforms | 8.9 (#2) | 7.6 (#18) |
| Audience | FlexBooks are designed for educators and students and cover K–12 topics. | The individual-user license is intended for people outside general education, such as university students or lifelong learners, and is for personal use only. |
| Headquarters | CK-12 lists its headquarters at 4300 Bohannon Drive, Suite 200, Menlo Park, California. | Tallinn, Estonia |
| Integrations | CK-12 lists Google Classroom, Canvas, Schoology, Kiddom, Clever and ClassLink as SSO or LMS partners. | Opiq can connect to eKool and Stuudium; teacher-assigned homework appears in those systems, and eKool teachers can import graded results. |
| Security | CK-12 says it uses administrative, technological and physical safeguards and encrypts transmissions with SSL or similar technology, while disclaiming a guarantee of security. | The maker’s data-processing agreement lists access management, authentication services, data encryption, and security testing among its safeguards. |
| Support | Users can contact CK-12 Support by starting a support ticket or sending an email. | Opiq lists support at [email protected] and +372 5323 7793, with phone hours Monday to Friday, 9–17. |
Plans
Opiq
- Päevikupakett€1 a month
- Algklassid ja eelkool (school license)€3.10 a month
- School package with e-lessons€4.60 a month
- Klassipakett€4.90 a month
- Erakasutaja 2026/27€15 a month
In their own words
CK-12 FlexBook 2.0
CK-12 FlexBook 2.0 provides customizable digital textbooks for K–12 subjects including science, math, and social studies. Lessons can combine text with PLIX interactives, simulations, adaptive practice, and related learning materials. Adaptive Practice draws questions from a library of more than 150,000 and adjusts selections based on student answers. Teachers can assign lessons, videos, interactives, and practice to whole classes or differentiated groups, then view progress reports. Educators can reorder chapters and edit or add content in customized FlexBooks. The service works in browsers on laptops, desktops, Chromebooks, tablets, and mobile devices, and is listed at free. Standalone Simulations and PLIX Interactives require a tablet-size screen or larger. Users may download PDFs of FlexBooks they create or customize, though interactive content may not render; CK-12-created PDFs are not downloadable. CK-12 says it is still converting all core content to FlexBook 2.0. Listed SSO or LMS partners include Google Classroom, Canvas, Schoology, Kiddom, Clever, and ClassLink.
Opiq
Opiq is a cloud-based learning environment and digital learning-material library for students, teachers, schools, and individual users. Its library contains more than 500 works from publishers and content creators, with materials described as aligned to the national curriculum and reviewed for facts and language. Teachers can assign tasks, create exercises, and track progress by chapter and student; many exercises are checked automatically. AI features find related material across subjects and textbook levels, while OpiqGPT combines chat with a language model and textbook text. Opiq connects with eKool and Stuudium for assigned homework, and eKool teachers can import graded results. It runs on Android, iOS, and web, with annotation and read-aloud support. A free plan is available, with paid access from €1/mo. The app requires an account, and paid licenses must be ordered on the website. Individual licenses are for personal use outside general education.