Hi! In my early youth - which occurred in the 1930s - the spellings center and centre were both in use. My Dad, a newspaper man, told me that at the time many were conflicted between the English spelling (centre) and the American (center) with the American version eventually coming into most general usage. Some teachers, for instance were of an older generation which used the English centre and passed it along to their pupils ... and, remember, these same older teachers were recalled to their jobs during WWII when the younger men and women went to war either in the Armed Services or in war-related jobs.
The Associated Press Stylebook, btw, requires center.
As to "colored" - it was used to refer to all "people of color" i.e. those not European white. I heard colored used well into my teens, mostly in regard to Negros, the word that gained prominence in post WWII years and changed little until the Civil Rights Movenment.
Neither was considered pejorative at the time but rather more polite than "colored."
Oh, will someone tell me what the prefered appelation is now? Pleeeeese.
(Feeling really out of date -econ)