Growing up in The Netherlands, we hardly learned about the US states, with all the geography ins- & outs. I don’t even know what are the capitals from all US states, let alone where every state is on the map.

By helping my kids to study for their geography bee, I learn a great deal more.
Sometimes I just would like to take a week off and bite my teeth into very basic stuff to learn. That way I would be able to help my kids even more. My interest would be primarily focussed on those black holes in my knowledge around the history & geography of the US states.
Furthermore, I have a big interest in learning the political system of the states and the federal government in the US. Not only the history of the laws but also how the actual system works. How do the house, the senate and the presidency work together making laws in the country.
I guess I could start with the study materials which are available to become a US citizen. This would be the basics.
As adults, we rarely stop and pause to learn new skills or knowledge. What are some of the things you would like to learn more about?