Re: Rocky and Bullwinkle... The machine was officially called the WABAC Machine (still pronounced "wayback" though), and even an old fart like me remembers seeing them in reruns as far back as the 1970's (when I was little, Sesame Street was still fairly new).

(no idea what the acronym "WABAC" actually stands for, though :) ).

Was the show originally asked about "Reading Rainbow", perhaps? (never really bothered watching it per se, but it sounds along those lines, and Wikipedia's entry for it tends to agree with the premise).