Is it As and Bs or A's and B's?
Category:
hobbies and interests
stamps and coins
It depends on the style manual you are following. The more conservative use is "A's and B's". The apostrophe does not show possession in this case. More recently I've seen "As and Bs" recommended.
Herein, is it straight as or straight A's?
straight As. the apostrophe is possessive, not plural. Tell that to the Oakland A's.
Consequently, why is there an apostrophe in A's?
Why do the Oakland Athletics use an apostrophe in the Oakland "A's"? When writing a single letter it is proper to use an apostrophe followed by an 's' to indicate plurals. So when "Athletic" is abbreviated to "A", it's plural form is in fact "A's".
Use an apostrophe and an –s to form the plural of all lowercase letters and the capital letters A, I, M, and U.