Be it as an etiquette session in 4-H, or likely in Home Economics class in high school (nowadays it is called something else; back in the day the vast majority of students for "Home Ec" were girls but a smattering of boys would enroll too -- sometimes you just had to fill a scheuling hole when other courses weren't available):<quoted text>
I was taught to lay my fork prongs down when finished.....not too many do that.
Placement and orientation of utensils when finishing eating were taught. At local diner eateries, I am admittedly slack.
Somewhere in time, I did pick up the European use of fork and knife when cutting/eating. It's certainly more efficient!