A teacher's website with many printables. There are also tools for making your own worksheets. Some are available for free, but a subscription gives access to more tools and interactive resources as well. (Fortunately, it's pretty easy to see what you can get for free and what you need a subscription for.)
Saturday Grab Bag
Printable curriculum materials for preschool through second grade levels.
Thursday History/Social Studies
This website from the Government Publishing Office has resources for learning about the US govern
The name of this site says it all!
Tuesday Language Arts
This company provides programs for beginning reading and math learning.
This company publishes three books for helping elementary learners explore science.
Self-paced, online courses for learning coding.