My heart aches for you, Bruce.
In about four weeks I will have my brand new 9th grade honors students do their first laboratory exercise. It is a simple getting to know the lab equipment sort of thing. One of the steps requires them to convert a measurement in centimeters to millimeters. For the metrically challenged, that means multiple by ten. Half of them will immediately reach for their calculators.
I have found it necessary to instruct some of my students on the correct manner of holding and using scissors. And measuring things (twice) before cutting.
If it makes you feel better, you are not alone. I just picked up a rather nice Conklin S3 (the same model used by Mark Twain from 1904-1907) in excellent condition from an online auction house not to be named for the princely sum of $22.00 US. The nib was in beautiful shape with lots of tipping, no cracks, no large scratches. All it needed was a simple resac. Why the bargain price? It was listed as a Cooklin. I found it by accident while looking for something else. A simpul speling misteak.