Americans are taught to spell in school the American way. Being an American, I learned to spell the American way. I wasn't perfect. I made some mistakes like using consistant for consistent, but at least I knew the difference between it's and its.
At church, we studied the Bible. It was regarded as our standard for living. I recall studying the Ten Commandments one day and noticing the spellings honour and neighbour.
My training-union teacher told me that they were just archaic spellings the way that the usage of thou is archaic. I initially accepted his explanation.
I noticed several other "archaic" spellings in the Bible. I made a game out of it: colour, shew, sceptre, &c.
It wasn't long before I came across some British comics. I forget the comic, but I remember the word, colour. When I asked my school teacher about it, she said that the spelling was indeed modern and used in Britain.
Argh! I thought, "The spelling is not archaic. How can we let the British guys spell words the Biblical way and let our nation spell it some heathenistic way?"
So I started spelling words like honour and colour the Biblical way (I did not deem it British) -- till I was penalised on my spelling tests.
Then I spelt words the Biblical way only for my personal use (such as letters) or when the teacher didn't count off for spelling only (science class), and also, as an act of rebellion, I started spelling words using any alternative spelling I could find in any dictionary: coöperate, centre, cancelled, phantasy.
Admittingly, I saw the weird spelling grey for gray, but I rejected it because I only saw women use it and deemed it a "sissy" spelling.
Other spellings I rejected because of my personal long-established usage: so I retained dialed, tire (not tyre), aluminum, and many others.
In high school, I was noticed for my weird spellings, and played the part. I used any word I could with a diacritical mark (naïvité was a favourite).
I even made up rules like any word which ends in -er in American and has a corresponding word ending in -re in French is spelt with an -re: e.g., lettre. That rule did not last too long.
Anyway, in my quest for novel spellings, I actually became quite a better speller for standard American spelling as well. I can be a good British speller too, if I could only learn some of their idioms (I could never find it in my heart to say "Let's get a move on" without a trailing "it".)
American dictionaries do not talk too much about the -ise/-ize alternatives in words such as recognise/recognize. The Oxford English Dictionary seemed to prefer -ize, and I seemed to have the impression that -ise was used only by the unlearnèd. (Also -ise is in the Epistle Dedicatory of the Authorized [sic] Version of the Holy Bible.) But then, one day I was at the Stone Mountain Confederate Memorial (east of Atlanta), reading a plaque and noticed the spelling recognised. At that moment, I deemed -ise the proper Confederate suffix and considered -ize to be just some Yankee infiltration into the language. I used -ise for all applicable words except baptize which is so spelt in my higher authority, the Authorized Version of the Holy Bible. Subsequently, I visited both Hong Kong and England where people were apologising and recognising, yet they rarely apologized or recognized. (As of June 2011, the plaque on Stone Mountain has been replaced with one that uses the spelling recognized.)
I still mix my -ise/-ize spellings around, depending on my mood.
By the way, I don't use shew, but I do use other Biblical archaic spellings such as carcase.
One spelling I've seen change as far as how common folk spell it is adaptor. Before 1981, I cannot ever recall seeing it spelt adapter, but the introduction of the IBM PC (whose documentation spelt it with the -er rather than -or) seems to have overwhelmingly changed its spelling. Even I look twice when I see adaptor, even though that is my personally preferred way of spelling it.
I still retain my dual spelling personalities: American schoolbook (with a few popular exceptions such as cancelled) for formal business purposes, and who-knows-what for personal use.
Linguistic concerns
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