Of the things I remember being taught, obviously Pluto, which I made a Papier-mâché model of in 6th grade as part of a class-wide model of the solar system. I guess I would still pass that. Other than that, the Soviet Union fell apart between 8th and 9th grades, so that was a shock, especially when countries started changing their names willy-nippy. And I've just learned about the fate of the poor Brontosaurus.
In first grade, we had a Dinosaur Week where the entire elementary school got together and pained a huge dinosaur mural on the playground. It felt cool knowing that a piece of me would be there forever as a reminder for future students.
It lasted 5 years before they tore up the playground to add an addition to provide new office space, and they build it right on top of where our mural used to be.
I can't even tell you how sad this makes me. At my school, there's this great Dr. Seuss mural on the Lower School wall that was painted by a senior class as their graduation gift to the school in the 70's. Not only is it still there, but every 10 years or so, the senior class will touch it up as part of their graduation gift. It' a great tradition.