CK-12 FlexBook 2.0 vs FlatWorld
CK-12 FlexBook 2.0
ck12.org
FlatWorld
flatworld.comSide by side
| Figure | CK-12 FlexBook 2.0 | FlatWorld |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| iOS | Yes | — |
| Android | Yes | — |
| Plans published | 2 | 3 |
| Spec score · Digital Textbook Platforms | 8.9 (#2) | 7.7 (#16) |
| Accessibility | CK-12’s 2024 VPAT states that the FlexBooks 2.0 platform meets AA conformance across the criteria covered by the report. | FlatWorld says its platform meets WCAG 2.2 Level AA and provides accessibility documentation including a VPAT/ACR. |
| Audience | FlexBooks are designed for educators and students and cover K–12 topics. | Its materials are designed for college and university instructors and students. |
| Customization | Teachers can customize and create FlexBooks, chapters and sections and add existing CK-12 content. | Instructors can reorder chapters, hide sections, and add custom material using FlatWorld’s textbook customization tools. |
| Headquarters | CK-12 lists its headquarters at 4300 Bohannon Drive, Suite 200, Menlo Park, California. | Boston, Massachusetts, United States |
| 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. | FlatWorld’s Trust Portal says it maintains an active SOC 2 Type II report and is TX-RAMP certified. |
| Support | Users can contact CK-12 Support by starting a support ticket or sending an email. | FlatWorld offers instructor support through a named representative and says support requests receive a response within 1–2 business days. |
Plans
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.