OTAN News

Discover Free Adult Education Resources on CK-12

The CK-12 Foundation offers free, high-quality, open educational resources that bring learning to life through digital textbooks, videos, simulations, and interactive activities.

Thanks to an ongoing partnership between CK-12 and OTAN, adult educators and learners now have access to a growing collection of FlexBooks designed specifically for adult education programs. These multimedia-rich, customizable textbooks support both in-person and online instruction, and they’re completely free.

What Is CK-12?

CK-12 is an online learning platform built around Open Educational Resources (OER) that educators can freely access, adapt, and share. Its FlexBooks combine engaging content with interactive features, including:

• Simulations and videos that make abstract concepts concrete
• Interactive quizzes and adaptive practice for personalized learning
• AI-assisted tools that support both students and teachers

Educators can easily remix content, upload their own materials, and integrate CK-12 directly into Canvas, Google Classroom, or Schoology.

CK-12 for Adult Education

Since 2021, OTAN and CK-12 have collaborated to create a series of adult education FlexBooks tailored for adult learners. The collection includes resources for Adult Basic Education (ABE), Adult Secondary Education (ASE) - High School Diploma and High School Equivalency, Career and Technical Education (CTE) and English as a Second Language (ESL), giving teachers a variety of options to enrich their programs.

Educators can also explore thousands of other CK-12 resources in any subject or grade level to supplement their instruction. Visit the CK-12 Adult Education site to start exploring these free materials.

What’s New for 2025: AI Tools for Teachers and Students

CK-12 continues to innovate with new AI-powered tools that make learning more interactive and personalized:

• Flexi, the AI Tutor – Students can ask questions and receive real-time explanations and feedback.
• AI Teacher Tools – Educators can generate practice sets, summarize content, and design differentiated learning paths to meet diverse student needs.

These AI tools enhance CK-12’s already-strong lineup of adaptive practice and interactive simulations, helping teachers save time while keeping students engaged.

How to Get Started

Getting started with CK-12 is simple, and free. Create an account, browse available FlexBooks, and customize materials to fit your learners’ goals. CK-12 also offers a Certified Educator Program, allowing teachers to learn at their own pace while earning badges for completed courses.

Explore how CK-12 can expand your teaching toolkit and empower your adult learners. With so many high-quality, interactive resources available at no cost, there’s never been a better time to get started.