This post has all of our free school textbooks for Grade 4, perfect for classroom and homeschool use, enjoy!
English Language and Arts Textbooks Grade 4
Grade 4 English including ELA, EFL, ESL, EAL, and all art related subjects.
Engage NY – Grade 4 English Resources US CCSS 
Grade 4 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-4-english-language-arts
*Note: ELA resources from countries which are bilingual or where English is not the national language may differ from those where English is a national language.
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Mathematics Grade 4
All grade 4 maths workbooks and textbooks
Grade 4 Maths Textbook RSA Syllabus 
This is a textbook for Grade 4 Maths from the syllabus in South Africa and includes a comprehensive teaching guide. This free school textbook for Grade 4 Maths is brought to us in creative commons, CC-BY-NC in the spirit of fostering open education resources (OER) for all. This textbook was developed and funded as an ongoing project by the Sasol Inzalo Foundation in partnership with the Ukuqonda Institute and with the participation of the Department of Basic Education of South Africa.
Ukukwonda Grade 4 Maths Textbook
Ukukwonda Grade 4 Maths Textbook Teachers Guide
Khan Academy Grade 4 Online Maths
This is a comprehensive selection of online lessons (videos, articles, and quizzes) for Grade 4 Mathematics. Khan Academy provides these 4th Grade OER resources for improving education. If students login there is progress tracking available, perfect for home school or extra tutoring:
Khan Academy Grade 4 Maths Online
CK-12 Grade 4 Online Textbooks Maths
This is a comprehensive selection of online lessons (explanations, images, worked examples, and interactive quizzes) for Grade 4 Maths. CK-12 provides these 4th Grade OER maths resources for improving education. The flexbooks provide an amazing customizable and interactive resource that can also be used offline.
CK-12 Grade 4 Maths Textbook and Practice Questions Online
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Science Textbooks Grade 4
All grade 4 science related textbooks.
Grade 4 Science RSA Syllabus 
These Grade 4 Science books are created by Siyavula for contribution to open education and are based on the Grade 4 Science syllabus in South Africa.
Natural Science Grade 4A pdf
Natural Science Grade 4A Teachers Guide pdf
Natural Science Grade 4B pdf
Natural Science Grade 4A Teachers Guide pdf
Natural Science Grade 4A and 4B ePub – CC-BY Unbranded
Natural Science Grade 4 Read Online
Grade 4 Science Utah Syllabus
This Grade 4 Science textbook covers the general science syllabus for Utah Grade 4. 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.
CK-12 Grade 4 Online Textbooks Science
This is a comprehensive selection of online lessons (explanations, images, worked examples, and interactive quizzes) for Grade 4 Science. Ck-12 provides these 4th Grade OER science resources for improving education. The flexbooks provide an amazing customizable and interactive resource that can also be used offline.
CK-12 Grade 4 Science Textbook and Practice Online
Geology Grade 4 Science and ELA
Geology – The Changing Earth is designed as a non-fiction reader for ELA grade 4, but can also be used as a science text for study in earth sciences. Students explore how different geological processes shape the earth’s landscape and related environments.
Geology Grade 4 -pdf
Geology Grade 4 – flipbook readonline
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Grade 4 Other Subjects
All grade 4 social studies, geography, history, and other subjects textbooks.
Grade 4 US Studies Michigan Open Textbooks
This Grade 4 US Studies 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 Studies textbook is suitable for 4th-grade level geography syllabus in Michigan.
pdf textbook – Grade 4 US Studies Textbook download
iBooks (may not be available in all countries) -Grade 4 US Studies iBooks textbook
Great resources, you have here.
Thanks, hope you can use them in your school.