I can remember learning This Land is Your Land in school (in Connecticut), but only the first two verses, not the more subversive ones that follow, of course. Also, John Brown's Body, but without being taught what it was about. Incidentally, they apparently learn that one also in parts of Eastern Europe; I can recall hearing a group of school children on a train in Czechoslavakia in 1967 singing, in English, "John Brown's body lies a mouldering in the grave."
Oh Susanna, Sweet Betsey from Pike, a lot of Burl Ives (Big Rock Candy Mt., The Blue Tail Fly, Old Dan Tucker, etc.), and yes, Stepehen (cringe) Foster.