I hadn’t heard of Big History, and this article in Aeon is actually critical of it, but it sounds interesting as an attempt to fuse natural and social science into a curriculum.
The Big History narrative itself is given shape by the interplay between the forces of entropy and complexity that are represented, respectively, by the second law of thermodynamics and evolution. The second law of thermodynamics postulates that there is a finite amount of energy in the Universe that is slowly dissipating, but evolution shows that there are moments when a particular threshold is reached and overcomes entropy by the creation of new forms of complexity. Big History proposes there are eight ‘threshold moments’, when profoundly new forms of complexity appear in the past: (1) the Big Bang; (2) stars and galaxies; (3) new chemical elements; (4) the Earth and solar system; (5) life on Earth; (6) the human species; (7) agriculture; and, our currently proposed geological epoch, (8) the Anthropocene.
Aeon
A lot of thinkers I admire, among them Howard T. Odum (not mentioned in this article), have focused on entropy as a sort of defining principle to understand the universe we find ourselves embedded in. Our universe is spirally toward disorder and randomness, but that process is very slow and somehow we find ourselves in a tiny pocket of increasing order within that universe. It starts with the Earth somehow orbiting the sun, and continues with life, the purpose of which seems to be to continue creating order out of chaos where mere physics and chemistry leave off, and then it seemingly culminates in intelligent life and the things intelligent life is able to create.
That’s my quick take from a skim of the article, but this article references a number of articles and books by the Australian developer of the Big History idea (the somewhat ironically named David Christian, because this is a system of belief at least somewhat intended as an alternative to traditional religion.) There is also a TED talk out there for people who like that sort of thing (give me a book, please), and apparently a middle- to high-school curriculum developed by the Gates Foundation.