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Scholastic Learn At Home allows open access to daily learning journeys divided into four grade spans—Pre-K–K, Grades 1–2, Grades 3–5, and Grades 6–9+, covering ELA, STEM, Science, Social Studies, and Social-Emotional Learning.
Zearn has made its K-5 math curriculum available for free to teachers. The content includes 400 hours of digital lessons. All you have to do is sign up as a homeschool teacher, and create a class with only your kids.
Legends of Learning has over 2,000 math and science games for grades 1-9. Follow the link and set up a student account for your child. You can also set up a parent account and track their progress.