On Mon 29 Dec 2003 11:47:11a, Jim Wilson wrote in
k.net:

No, it's not wrong. The apostrophe is fine in examples like Sylvan's
"straight A's."

There, see? They changed it while I wasn't looking again! In high school I
was told in no uncertain terms, it's straight As, not A's, it's SATs, not
SAT's, and now here's you, and this guy:
http://newark.rutgers.edu/~jlynch/Writing/a.html

Ya take your eyes off the grammar book for a measly ten or twenty years and
look what happens.
:-)