Except that, I know I’ve seen “mathematics” used as a plural, at least once or twice, in something an English person has written.
That’s if you’re using “math” to mean “the kind of thing mathematicians do.” There are other perfectly legitimate meanings for the word (kind of like there’s more than one meaning for "writing).
The word “arithmetic” (with or without the modifier “higher”) is an old-fashioned term for what is nowadays more commonly referred to as “number theory.” It’s also a slightly less old-fashioned term for numerical calculation (addition, subtraction, multiplication, division): one of the “three R’s” of elementary school. I gather this is also referred to in England as doing “sums,” though to me, as an American, “sums” implies addition only.
Way back in COBOL programming days, I was taught the following algorithm for making abbreviations:
- repeat until short enough.
- apply to all words involved.
- start from the right & move to the left.
- remove one of all double letters. Tennessee becomes Tenese
- remove vowels (but not the 1st letter of a word). Tenese becomes Tns
- remove consonants. Tns becomes Tn
This seems to work pretty well in most cases. These rules seem to have been followed in creating many common abbreviations. But, many of them don’t. Like many parts of the English language, there are often nearly as many exceptions as those that folloe the rules.
‘Doing sums’ is so loose a colloquialism that it’s best not to try to extract any literal meaning out of it (a little like the way that the phrase “you do the math” turns up in comparative contexts that don’t involve any numerical judgment or calculation at all)
The -ic suffix is orginally adjectival, and it is still frequently used to construct adejectives - oceanic, Icelandic, domestic. It comes into English, via Latin and French, from Greek (-ikos). But, also following Greek, since forever English has seen those adjectives evolve into nouns - physic, stoic, critic logic, magic. In Greek, if these nouns had masculine gender they referred to an individual - a stoic, a critic, a cynic; if they had feminine gender they referrred to coherent systems of thought, knowledge or action - music, rhetoric; and if they had neuter gender they were used in the plural for diverse collections of matters or affairs relevant to a a common theme - economics (various things relevant to household management). This elegant scheme enabled quite subtle distinctions - politic, the art of statesmanship versus politics, public affairs in general.
But in the transition to Latin, to French, to English, the sharp distinctions were lost, in particular the distinction between a coherent body of thought, and a collection of disparate subjects with a common relevance. New words were coined on the same model, but without observing the gender and number distinctions that the Greeks had observed - avionics, acoustics - or words which had been singular in Greek were pluralised on their way to English - ethics, mathematics (but not, curiously, arithmetic). The pluralisation usually happened in Latin or French, and in those languages the words were (and still are) treated as grammatically plural (les mathématiques) but some time around the seventeenth century English reverted to treating them as singular, presumably for conformity with the -ic words.
And this is why I love the Straight Dope.
Thanks.
All Ohio counties are divided into townships (as square-like in shape as possible)and any location that is unincorporated—that is, not incorporated as a city or a village—is governed by a township, which is a vast majority of the state’s territory.
Related sort of: I’ve always wondered why the Brits say “the” calculus, as in “Sir Isaac Newton invented “the” calculus.”
Likewise with “Bring ye one pint of water to “the” boil.” Not just any boil, govna. But * the* boil.
I suppose it’s because there are other calculuses, but that one is The Calculus.
We don’t say “the calculus”, an archaic name for calculus is “the calculus of infinitesimals”, but that’s not used in UK any more than it is in the USA. “The calculus of variations” is a term still used in the UK and USA, maybe the USA has more of tendency to drop the definite article in this term, but I don’t know.
We don’t. I’ve never heard anyone call it that.
OK, that one, we do - doesn’t everyone? What about “off the boil”? (i.e. as an idiom for something that has peaked and is cooling off).
No. You bring water to a boil here in the U.S. And I don’t think we have an idiom like that using “boil.”
Really? So how do you know which boil to bring it to? 
Interesting. I guess we say that too in some formations ‘a steady rolling boil’ or ‘a fast boil’, for example. I think the definite article is actually an unconscious contraction of ‘bring to the [point of] boil[ing]’, or something like that.
‘Bring to the boil’ is usually succeeded by some immediately following action, i.e. ‘then turn down the heat and simmer’. I think that is also part of the logic.
Nothing like “of course the divorce was inevitable; their marriage had been off the boil for several years”?
My WAG is that ‘Maths’ simply fits better into a timetable chart as there is no accepted abbreviation for ‘arithmetic’. ‘Math’ is an American version that has crept into the language, like so many others.
Teachers do not really think too much about this kind of stuff. In fact, if my children’s reports and letters from school were any guide, they are pretty grammatically challenged for the most part. I was tempted on a couple of occasions to send a letter back with red ink marking the errors.
I’ve never encountered that in American usage.
Newton’s calculus is also sometimes called “Calculus of Fluxions”. And while the term “Calculus of Variations” is in use, it refers to a different field (related, but more advanced), that of finding functions which minimize some figure of merit.
Fair enough. These things don’t tend to male greater sense in response to deeper scrutiny. Its just one of those things that is the way it is, because it is. If there was a hard and fast rule, Jack Kerouac’s book might have been titled ‘On A Road’ (or possibly ‘On Some Roads’). 
I’m reviving this thread to post a link: Why Do Brits Say Maths and Americans Say Math?
“TWP” and “township” is the basis for the entire Public Land Survey System (PLSS), essentially the way everything west of the original 13 colonies is divided up (generalizing here, not 100% accurate). As such, the term and abbreviation factor heavily in the lives of anybody involved in survey or land records in those areas.
A PLSS township is a six by six grid of one square mile sections, arranged boustrophedontically- section one through six along the northern edge of the township from east to west, then seven to twelve under that from west to east, rinse, and repeat for all thirty-six sections.