Okay, but this seems to make the same mistake as the French education system, who talks about foreign "languages" in general.
But most non-English-speaking people don't want to learn "languageS" as if those were all equivalent and there was some general quality to be gained by speaking different tongues. They want to learn English, as the only international language.
I want my kids to speak English not because they'll have a better mind if they do, like I try to have them learn music, but because not speaking English in today's world is like missing an eye (or more probably both).
As for why English-speaking people want to learn a foreign language, I have no idea, but I suspect their motivations are wholly different. It's interesting to speak Spanish, it's mind-opening to learn Chinese, but it's not vital.
So what I'm looking for is a "system" aimed at young / very young kids, specialized in teaching English (and only English).
To succeed it needs to be playful, maybe addictive, not require one to already know how to read -- and in general not look or sound like anything "school-y".
Somebody (was it John Holt?) said "if we taught kids how to speak, they would never learn". Yet that's exactly what we're doing with foreign languages.