For example,
The school has just started an SLA program.
(SLA is second language acquisition.)
Should I use "a" instead of "an" here? Technically, following the rules of "an", I should use "an" here since the acronym starts with a vowel's sound. However, I'm not sure if acronyms are even considered words, which means these rules might not apply to them. If I expand the acronym, I realize I should use "a", which leaves me a little confused. Do I have it right or should it be "a"?