HAHAHA I remember that Barb! It actually frustrated me a bit though...that show was awful with continuity...but I think they went too far with Eric. I mean, for most of the series, he was a tad vain but went through his own problems as Cory did and could be a really interesting character. By the last season, they just turned him into a Feeny-worshipping airhead. Some of the things they had him do...like set fire to something for Cory's wedding...watch the early seasons, that's not what he would have done. Ulgh, very frustrating.
(Sorry to do slight threadjacking).
Hmm, I'll do a bit of thinking, it's very possible that there could have been a time where we could have heard him sing. There were definitely group singings of happy birthday and such but that wouldn't really help...
"If there was a Mount Rushmore for Broadway scores, "West Side Story" would be front and center. It snaps, it crackles it pops! It surges with a roar, its energy and sheer life undiminished by the years" - NYPost reviewer Elisabeth Vincentelli