The 4 year olds may be too young,but I am a big fan of teaching how we got here.
I gave a 6 session course to a homeschool coop on the History of Technology starting from stones and moving through bronze age, iron age, steam power, electricity, telegraph demo (big hit) radio and TV and early computers.
(I think Engineering schools should have a course on tech history)
Not really I cobbled together some notes from Internet content.
Of note since it was a church based group, I referenced ancient time to biblical figures and the estimated dates of their time because they new of these characters. (I had to puncture the 6,000 year old earth idea, but I didn't hear complaints from parents so I guess they are not in that camp)
I gave a 6 session course to a homeschool coop on the History of Technology starting from stones and moving through bronze age, iron age, steam power, electricity, telegraph demo (big hit) radio and TV and early computers.
(I think Engineering schools should have a course on tech history)