https://www.doh.wa.gov/Emergencies/NovelCoronavirusOutbreak2020/HealthEducation
Award-winning reading solution with thousands of leveled readers, lesson plans, worksheets and assessments to teach guided reading, reading proficiency and comprehension to K-5 students
Elementary:
https://www.fredisalearns.com/english-courses/
Highlights Kids - The place for children of all ages to play games and discover new jokes, surveys, answers to science questions, and fun crafts and recipes from Highlights.
Learn English Today - ESL Gold
Reading has always been a great way of learning and building upon the knowledge of the great thinkers in a particular language. As you learn to read English, you will have access to a whole new world of information, people, and culture.
Starfall Education: Kids Games, Movies, & Books K-3
At Starfall, children have fun while they learn - specializing in reading, phonics & math - educational games, movies, books, songs, and more for children K-3.
5th+ grade plus:
BBC Learning English - BBC Learning English - homepage
Learn English with these free learning English videos and materials from BBC Learning English. This site will help you learn English and improve your pronunciation, grammar and vocabulary knowledge.
Grammar | Arts and humanities | Khan Academy
Grammar is the collection of rules and conventions that makes languages go. This section is about Standard American English, but there's something here for everyone.