In this 1949 filmstrip, we learn the positive effects of good posture on all aspects of a student's life. If you're looking for a study on mid-century American attitudes toward success in life, this is required viewing. It even includes a set of posture practices to do with your buddy, awkwardly staring at one another, balancing books on each other's heads, checking each other's calves, and so on.
The sound on this filmstrip is a bit mangled, but it's good enough to make out lines like, "Without poise, no one can be really attractive." This comes just before a young lady walks down her front steps to leave for a date. Then, oddly, the whole thing veers into a discussion of the "seven basic foods," one of which is, no kidding, "bread and butter." Oddly, another left turn in the narrative brings us into a discussion of functional exercise based on group dance exercises. I suspect that this might be because the producers happened to have some footage of group dance exercises lying around.
Posture is important, kids. But let's be thankful that this is not how we learn about it anymore.