K–12 learning platform · independently evaluated

CK-12

Free K–12 learning with digital textbooks, flashcards, adaptive practice, simulations, and Flexi support across math and science.

Science · Math · Parent & educatorAges 10–18Free🌐 1 languages

Website Android app

Website preview

About CK-12

CK-12 offers free K–12 learning through digital textbooks, flashcards, adaptive practice, simulations, and Flexi, its AI tutor. The student landing page organizes access around courses, subjects, FlexBooks, and study help.

Age and access

This resource is listed for ages 10–18. It is available as Website, Android app and is listed as free. The listed language coverage is English.

What stands out

FlexBooks and simulations support deeper study than short quizzes alone
Math and science content is organized for K–12 learners
The official footer provides a direct Google Play listing for Flexi

Evaluation detail

How the score is built

Academic breadthStrong

The student page connects courses, FlexBooks, practice, simulations, and Flexi support.

Age fitClear

The provider explicitly presents the platform for K–12 learners.

AccessStrong

The public learning platform and FlexBooks are free to explore.

Platform evidenceStrong

The official footer directly links the Flexi Android app.

For grown-ups

Parent notes

The public student page includes sign-in and class features, so account requirements can vary by activity.
The official source shows an Android app link and an iOS home-screen help route, but no verified Apple App Store listing was added.
The stored preview is the official student page without a cookie popup, ad overlay, broken rendering, or placeholder imagery.

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