Actually, the Malibu Stacey episode came from the "Teen Talk Barbie" of 1992, who could say four out of 270 sentences. One of those was "Math class is tough!".
It's not what she's saying, it's the transparent babydoll top she's wearing that I would hate for my niece to wear before she reached adulthood...
I remember this ad. I don't think I had this particular Barbie doll, though. I had lots of others! Sue me, I like Barbie. :)