Almost all history classes before college give the impression of history as one big logical progression, from the unhappy and unfair past to the completely and utterly perfect present. The suggest that the victories of the current ideas about morality and economy--basically, "Everyone's equal" and "Capitalism wins"--were inevitable, and will last forever. It's as though the textbook writers see the whole thing as a big story, and they decided to remove all tension, moral ambiguity, and give the whole thing a nice big happy ending.
Not that I'm bitter, or anything.