https://www.freckle.com/

Math (K-9)

ELA (K-12)

Social Studies (1-12)

Science (K-8)

"Freckle empowers teachers to differentiate instruction across Math, ELA, Social Studies and Science."

A truncated version, is available free of charge for individual teachers. With the free version, it is recommended that teachers print/save PDF of progress weekly since there is not storage with the free version.

https://readtheory.org/

Reading (K-12)

"ReadTheory's adaptive approach fosters improvement by automatically meeting learners at their own, individual ability levels. Signup takes seconds and no time is spent vetting assignments. Progress is shown on an intuitive report, replete with actionable, meaningful insights. Our program is completely free."

https://www.readworks.org/

Reading (K-12)

"Free reading content, curriculum, and tools to power teaching and learning from Kindergarten to 12th Grade"

https://www.readinga-z.com/

Reading (K-5)

Teachers may access free samples and a free trial.

https://www.getepic.com/educators

Reading (K-5)

"Thousands of Amazing Kids’ Books

FREE for teachers & librarians

Instantly Access 35,000 eBooks, Learning Videos, Quizzes and more for K-5."

https://www.mobymax.com/moby-learning

Reading (K-8)

"Register for our free version with absolutely no obligation.

MobyMax combines award-winning curriculum covering 27 K-8 subjects with diagnostic testing, automatic progress monitoring, student motivation tools, communication tools, and more."

https://www.worksheetworks.com/

Reading (K-12)

There are some free worksheets. Yearly fee for individual teachers for full access.

"We do worksheets. Some people call them “printables.”. On our site, you, the user, get to choose what goes into your worksheet. Every “generator” has options to make the worksheets you need. Depending on the topic, you can control different aspects such as the problem difficulty, the kinds of problems asked, and even the appearance of the page. The worksheets that you download from WorksheetWorks.com are made just for you."

https://www.noredink.com/

Grammar and writing (K-12)

A truncated version, is available free of charge for individual teachers.

"We believe that “playing with language” is an essential part of learning to write. That’s why we have students drag in commas, click words to capitalize them, throw out unwanted punctuation, and edit parts of sentences directly whenever possible. We also design exercises that have multiple correct answers, as there’s more than one way to write a sentence. NoRedInk builds stronger writers through interest-based curriculum, adaptive exercises, and actionable data."