CK-12

自由，有趣的方式学习数学和科学

With the free CK-12 app for phones and tablets, you’re in control of learning. CK-12 features 5000+ math and science lessons and concepts - all accessible anytime, anywhere. All content is created and curated by teachers, for students. Whether you’re looking to improve your grades, or brush up on your favorite math or science topics, CK-12 has you covered - for free! We’re the go-to resource for K-12 STEM education.

Features:

* Practice & Learn at your own pace

* Track and work on your class assignments.

* Receive reminders for upcoming assignment deadlines.

* Choose from a comprehensive library of elementary, middle and high school concepts in math and science, or search by keyword.

* Thousands of math and science quizzes

* Easily track your progress on all subjects

* Improve over time and see your progress with reports

* Get recommendations for learning resources

* Advanced diagnostic and remediation to help you get through your practice and assignments

* Videos, simulations, interactives, real world group activities & more!

Topics covered:

- Elementary Math:

* Addition, Subtraction, Multiplication and Division

* Time

* Measurement

* Geometry

* Place Value

* Decimals and Fractions

* Money

* Factors and Multiples

* PEMDAS

- Math:

* Arithmetic

* Measurement

* Algebra

* Geometry

* Probability

* Statistics

* Trigonometry

* Analysis

* Calculus

- Science:

* Earth Science

* Life Science

* Physical Science

* Biology

* Chemistry

* Physics

- English

* Spelling

See all of our learning resources, including free digital textbooks, at http://www.ck12.org

Don’t forget to check us out on social!

https://www.facebook.com/CK12Foundation

https://twitter.com/CK12Foundation

https://plus.google.com/+Ck12Org/

https://www.pinterest.com/ck12foundation/

About CK-12

CK-12 is a non-profit that creates and curates high quality STEM content for students and teachers around the world. The organization was founded with the mission to enable everyone to learn in his or her own way - for free.