Frank Lloyd Wright's gas station in Cloquet, MN earlier this summer, N. suggested we check out an unusual gas station closer to home: the Shell Service Station, which was built around 1930 by Frank L. Blume & Co. to draw attention to the Shell Company. There were once 8 of these stations in our city; this is the only one remaining. It is listed on the National Register of Historic Places and was recently restored. The structure is a bent-wood frame covered with hand-sculpted concrete (N. was surprised that the frame wasn't made of metal).
Here's a "lesson plan" from the National Park Service on Roadside Attractions that starts with this station and includes some other odd American novelty buildings. I read somewhere that this was the first gas station to be listed on the National Register of Historic Places, but I don't know if that's accurate.
I'm adding Gas Stations to my ever-growing List of Things I Never Thought I'd Be Interested in Before I Had A Son and Started Homeschooling!