I wish we were taught to think on various base number systems from a young age. I imagine there could be elegant solutions to many problems currently being hidden just out of sight.
I could be mistaken, but I believe in the US that elementary school mathematics is now addressing the concept of arithmetic base at an earlier age. Unfortunately I've mostly heard about this in the context of parents complaining about the curriculum probably because they don't understand the topic.
I taught base-10 to my kids (pre school, ie 3/4) by teaching them the concept of number bases, and considering aliens with different numbers of fingers ... and robots of course (my robots only speak binary!). Seemed to work somewhat.
Mind you, despite having relatively good teaching in mainstream UK schooling they could all definitely have done/do with more headroom in their school maths.