Yeah the 3 bears song is really cute isn't it? I enjoyed the 'Full House" drama also, but did you know that in it there is one scene where the guy says he is going to sing it like "an American" and he purposely messes up the pronunciation? That scene was, unfortunately, unflattering to foreign students of Korean and reinforced the stereotype that all "Americans" pronounce Korean poorly.
Yeah, it's cute, together with the actions. Yes, the part that Rain sings in American version.
I would be fun and great if we (KC101.com) have a few video clips of them.
I learned that song from a free iPod Touch app called Rhythm Songs by JPL media.