This is a collection of math and programming resources collected by some education-centric folks who have done several year-abroad trips over the years with their kids.
It might be useful for folks who’s kids are out of school.
I would also add Math from Three to Seven: The Story of a Mathematical Circle for Preschoolers to the list. It’s a great resource for the teacher/parent rather than the child on how to run a Math circle. I’m only a few chapters in but I’ve found it to be a great source of ideas and inspiration for engaging a 6 year old and a 3 year old. Unfortunately our circle is small.
I highly recommend Dragon Box Algebra. It’s amazing. My review here: https://www.google.com/amp/s/kaushikghose.wordpress.com/2019/10/27/dragonbox-algebra/amp/