This post contains all our free grade 8 textbooks, workbooks, and worksheets. These open education resources are perfect for classroom or homeschool use, enjoy!
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Grade 8 ELA Textbooks
Below are all our English Language and Arts free school textbooks.
Engage NY – Grade 8 English Resources US CCSS 
Grade 8 English Language resources, lesson plans, reading and writing exercises and questions, released as OER in CC-BY-NC. Note while the lesson plans in this content are free, many texts they are based on are copyright and have to be purchased or obtained from a library. While there are some free copies around, the texts are copyright so cannot be reproduced or linked here.
https://www.engageny.org/resource/grade-8-english-language-arts
Grade 8 English Textbooks India *
Grade 8 English Textbook, Honeydew, and supplementary reader It so Happened, for the Indian national syllabus Class 8, released as OER in CC-BY-NC.
Grade 8 Honeydew textbook – Download zip file of pdf Chapters
Grade 8 It So happened Supplementary Reader – Download zip file of pdf Chapters
All NCERT Textbooks Read Online – Pathshala
Grade 8 English and Art Textbooks Fiji *
Grade 8 English Textbook, created for the Fijian national syllabus Class 6.
Grade 8 English textbook – download pdf
Grade 8 English textbook read online – Preview in Browser
Grade 8 Art textbook – download pdf
Grade 8 Art textbook read online – Preview in Browser
Punjab – Grade 8 English Activity Book*
A well presented Grade 8 English Language activity textbook from the Government of The Punjab. These resources make great ESL printables too.*
Grade 8 English textbook from Punjabi – pdf
*Note: ELA resources from countries that are bilingual or where English is not the national language may differ from those where English is a national language curriculum, however, student English levels can vary significantly too, you can always look one or two grades up or down to find resources that fit your needs.
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Grade 8 Maths Textbooks
Below are all our Grade 8 Mathematics free school textbooks.
These are four Grade 8 level textbooks provided by Open Schools BC on the modules as outlined below:
Maths Grade 8 Module 2 – Squares, Integers, and the Pythagorean Theorem – http://media.openschool.bc.ca/osbcmedia/ma08/etext/Math8_mod2.pdf
Maths Grade 8 Module 3 – Data, Graphing, and Linear Equations – http://media.openschool.bc.ca/osbcmedia/ma08/etext/Math8_mod3.pdf
Maths Grade 8 Module 4 Fractions, Ratios, and Probability – http://media.openschool.bc.ca/osbcmedia/ma08/etext/Math8_mod4.pdf
This is a collection of 3 Maths open textbooks for Literacy Foundations Math Level 6, Grade 8, released under Creative Commons, the textbooks provided here include Number Sense, Patterns and Relations, and Geometry.
Number Sense Math Textbook Level 6/Grade 8 – http://media.openschool.bc.ca/osbcmedia/math/math6/etext/LF_MathL6_Number.pdf
Geometry Math Textbook Level 6/Grade 8 – http://media.openschool.bc.ca/osbcmedia/math/math6/etext/LF_MathL6_Geometry.pdf
Patterns and Relations Math Textbook Level 6/Grade 8 – http://media.openschool.bc.ca/osbcmedia/math/math6/etext/LF_MathL6_Patterns.pdf
Grade 8 Maths RSA Syllabus 
These Grade 8 Maths books are created by Siyavula for contribution to open education and are based on the Grade 8 Mathematics syllabus in South Africa.
Mathematics Grade 8A pdf
Mathematics Grade 8B pdf
Mathematics Grade 8 Read online
8th Grade Maths Textbooks – Utah Syllabus
These middle-grade mathematics textbooks cover the maths syllabus for 7th grade (middle school) in Utah. It is created by Utah Education Network open textbooks project for contribution to open education, they are licensed CC-BY-NC. The books are available as separate chapter downloads each subject has a set of three books including a foundation book covering concepts, a workbook for students, and a teacher/parent guidebook.
Middle Grade Maths 8th Grade Textbooks Utah
CK-12 Grade 8 Online Textbooks Maths
This is a comprehensive selection of online lessons (explanations, images, worked examples, and interactive quizzes) for Grade 8 Maths. CK-12 provides these 8th Grade OER maths resources for improving education. The flexbooks provide an amazing customizable and interactive resource that can also be used offline for K-12.
CK-12 Grade 8 Maths Textbook Online
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Grade 8 Science Textbooks
Below are all our Grade 8 Science free school textbooks.
Grade 8 Science RSA Syllabus 
These Grade 8 Science books are created by Siyavula for contribution to open education and are based on the Grade 8 Natural Sciences syllabus in South Africa.
Natural Science Grade 8A pdf
Natural Science Grade 8A Teachers Guide
Natural Science Grade 8B pdf
Natural Science Grade 8B Teachers Guide
Grade 8 Natural Sciencecs 8A and 8B epub – CC-BY unbranded
Grade 8 Science Utah Syllabus 
This Grade 8 Science textbook covers the general science syllabus for Utah Grade 8. The content is sourced from CK-12 Foundation, and the book has been created by Utah Education Network open textbooks project for contribution to open education, they are licensed CC-BY-NC.
Grade 8 Science Textbook pdf download – Utah Education Network
CK-12 Middle-grade Online Textbooks Science
This is a comprehensive selection of online lessons (explanations, images, worked examples, and interactive quizzes) for life sciences, physical sciences, and earth sciences for middle school. CK-12 provides these resources for middle school, grades 6, 7, and 8, science for improving education. The flexbooks provide an amazing customizable and interactive resource that can also be used offline.
CK-12 Middle School Earth Science Textbook Online
CK-12 Middle School Physical Science Textbook Online
CK-12 Middle School Life Science Textbook Online
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Grade 8 Other Subjects
All grade 8 social studies, geography, history, and other subject textbooks.
Grade 8 United States History Michigan Syllabus 
This Grade 8 United States History textbook was created by Michigan Open Textbooks Project for contribution to open education resources and by sponsorship from the Michigan State Education Department. This US History textbook is based on the Grade 8 United States History syllabus in Michigan.
Grade 8 United States History
pdf textbook – http://textbooks.wmisd.org/Downloads/8th/8thGradeUnitedStatesHistory-RevolutionThroughReconstruction.pdf
ibooks (may not be available in all countries) – https://itunes.apple.com/us/book/id1133204497
Your link to middle school life science does not work. It should be https://www.ck12.org/book/ck-12-life-science-for-middle-school/ which does work
Thank-you for your input, I have updated the link