She appeared on Mister Rogers Neighborhood!
interesting video
https://www.youtube.com/watch?v=vEY5EkUR6_M
and sesame street
https://www.reddit.com/r/lostmedia/comments/vf7yu2/found_sesame_street_847_margaret_hamilton_wicked/?utm_source=share&utm_medium=web2x&context=3
A long lost episode of "Sesame Street" from 1976, deemed "too scary" by parents for featuring Margaret Hamilton as the Wicked Witch, has at last been found and preserved by the Library of Congress.
https://www.avclub.com/lost-wicked-witch-sesame-street-episode-online-1849081598
https://www.reddit.com/r/television/comments/vfsvsk/a_long_lost_episode_of_sesame_street_from_1976/