At the age of 13, before starting 9th grade, I had to choose a language course. This being 1970s Pittsburgh, the choices were Spanish or French.
The Spanish teacher was a huge, surly, old battleax. I believe at that point she'd been teaching for 80 or 90 years. She yelled at her students, gave way too much homework, and expected them to actually learn what she was teaching them. Her reputation spread far & wide among terrified high school students.
The French teacher was rumored to have posed in Playboy. Her reputation also spread far & wide among a somewhat different group of students & parents.
You can guess which language I chose to study for the next six years. I even have top marks in a Defense Language Proficiency exam. However I've never had a reason to use it and I've never lived in a country where it was spoken. About all I can say is that it got me through the mandatory language requirements and it taught me how to speak better English.
My spouse spent five years studying Spanish. Her first duty station after college was... Spain. That was followed by Portugal (the Azores), Monterey, Hawaii, & San Diego. She's hardly ever stopped using her Spanish.
If I had to do it all over again I'd choose Spanish or Japanese-- languages that I might actually use someday.