I really have to wonder what sort of school you were teaching at. That certainly was not the case at any school I attended.
This, of course, is why anecdotal “evidence” is pretty useless. I’ll see you one “my [American] college students [with] panicked looks” with one “my [American] college students are perfectly able to convert measures as needed” and raise you one “and my [American] fifth graders are perfectly comfortable with the notion that feet, inches, and miles are all measures of length.” (I suspect that my American second graders are as well but I’m not positive as I’ll admit I haven’t ever asked them :).)
I’ll also point out that just because 5th graders “in the rest of the world” SHOULD be able to convert easily doesn’t mean that they can. I’ve written before here about why it may not be a great idea to rely heavily on international tests to determine the effectiveness of a country’s educational system. But it may be worth pointing out that, any difficulties with measurements notwithstanding, US fourth graders on the 2015 TIMSS test scored well above same-age kids from France, Spain, Italy, Australia, Canada, Sweden, and New Zealand, to name a few where kids supposedly don’t have these troubles.
In grade 8, Canada actually did slightly better than the US and a few of these other countries didn;t take the test, but the US still outperformed Australia, Italy, Sweden, and New Zealand by a good margin. [See Distribution of Mathematics Achievement – TIMSS 2015 and TIMSS Advanced 2015 International Results] Again, this does not mean that US kids are necessarily “better” at math than kids in New Zealand or Sweden, for a variety of reasons; but it certainly isn’t consistent with the notion that they are notably worse.
So, either it’s possible for kids to succeed despite not knowing anything to speak of about measurement, or we should be really careful about putting much weight on anecdotal evidence as an, um, measure of anything. Or maybe, some of both :).
Awhile back I was staying in Sweden with a professor who taught American college students in summer-abroad programs. I asked her what was different about Americans (from, of course, Swedish students). She thought for a minute and said, “well, they eat like children.” This is the knife and fork thing.
And then she said, “and they ask so many questions!”
She enjoyed her American students because unlike her Swedish students, they were not afraid to ask basic or even stupid questions, and pursue the answers. Likely part of this was a self-selected group of students, but still, I felt rather charmed.
The Imperial measuring system is inferior because it means you can’t have cool names for things like the Royal with Cheese 
The point of having standard measures is not that one length is better than a slightly different length, or that a unit divisible by 10 is better than one divisible by 12 or 14 or 16. The advantage of a standard measure is that everybody uses it.
ETA eg that way you do not have to buy both Letter and A4 paper for your office printer, or worry about whether your engineer used wine gallons, imperial gallons, or U.S. Gallons for a critical calculation.
[ETA cont’d] I had a lot of “fun” once discovering the difference between American and British non-metric bolts. Also, at least one spacecraft has been lost due to confusion between different units, but I swear I had nothing to do with that.
I don’t know if its true or not but I’ve been told that its customary in Europe that bathroom doors are left closed, even when unoccupied. In the U.S. they are left open or ajar.
HA! Shows how much you know! The improvement is properly measured by mass, not volume!
So 1.75 terapounds. Negative, unfortunately.
Give it up. Your arguments ultimately boil down to “You’re wrong because I’m right!”, and they convince no one. Not even someone who actually agrees with you, such as me.
We see a mix of this from kids friends who come over. I’m always baffled how “closed door” families figure if the bathroom is available without knocking.
I can see this in Europe since I believe they have the light switch on the outside.
We’re a closed door family, not because we’re European nor because of light switch location, but because the cat simply loves to puke on bathmats. We know the room is not occupied if the door is unlocked.
Ugh, I’ll take vomit over pee any day. World’s most stress free cat, but he considers bathmats a target. As his actual bathroom is in there I can’t close it and wouldn’t otherwise, so the mat lives hanging off the shower curtain rod when not in use.
Yeah, we don’t have any rhyme or reason. The door might be closed when unoccupied; it might be open. I’ve never really noticed people being completely consistent about keeping the door ajar if it’s unoccupied. I don’t assume a closed door means nobody’s in there. I’ll knock and see. I’ve also not noticed this to be an American vs non-American thing.
As a family of six with 1.5 bathrooms, we seem to have settled into a pattern out of practicality.
Which is why they standardised on UNC. Then at the last moment, the British decided that they would adopt the Metric standard instead of the UNC standard they had been working on, (Both UNC and Metric use modern thread design. Older systems used older thread designs. Both Britain and the USA had older bolt standards).
Of course there was a little quid pro quo: the “Metric” standard for pipe threads in actually British Standard Pipe, with a new name. No more (or less) metric than the standard inch.