In 1991, HBO dived into the Saturday morning cartoon arena with the anthology series, Animated Hero Classics. In all, 20 episodes were produced between 1991-2004, which doesn't really put any bite to HBO's commitment to children's educational programming. Today, HBO shares the rights to Sesame Street, with episodes repurposed on the series' long-time broadcast home, PBS, but it's not quite the same as the lip service HBO gave to the government back in the 90's.
Following is the bio on Alexander Graham Bell. The open & close have been edited off.
Even though this was a Saturday series, since this is HBO we're talking about, it likely was rebroadcast on different days and at various times.