My middle school started you on French, Spanish, or American Sign Language in 7th grade. (From what I know ASL isn't a joke language but has its own grammar, et cetera, and is basically useless unless you're to be working with the deaf.) I got a lot out of it, though I was a C student well into high school until I got good at it. That system works well, I think. Obviously exposure to the language is taken at a nice easy pace, both to marinate it and to learn all the grammar they no longer teach in English class.
I started Latin about a decade too late, after the easy-language-learning circuitry had been switched off. Started Greek a year or two later. It's just a hobby that I'll probably never be great at but which can be a lifelong pursuit and which brings me pleasure and, as important, mental stimulation.