Metadata for educational content is very hard to come by.
Maybe these videos are also available here? https://www.youtube.com/hookedonphonics
Or maybe you can find descriptions etc. on their website: https://www.hookedonphonics.com
My guess would be that the only viable way would be to create .nfo files for these videos. Then use the new support for nfo files in a dedicated TV Show library in Plex: https://forums.plex.tv/t/plex-nfo-agent-forum-preview/936104/1
