Our family travels a lot, but our son who is just 6 years old doesn't remember all the trips. However, we've been studying the United States just to acclimate him to the places we mention that we've been or places where relatives live.
I bought a map from the Dollar Tree of the United States. We've been putting it together while discussing road trips and attributes of each state.
We discovered a youtube channel Called Socratia.
Here's an example of a states video we watched.