Monoshiri Daigaku Ashita No Calendar was an educative anime than it was trasmited between 1966 and 1975, It was one of the first series than it was trasmited exclusively in TV. It is also one of the longest animes in all the history, counting with more of 1.200 chapters
Lost thougth years
In 1975 the anime got cancelled by the bad preservacion of the episodes, resulting with the lost of some episodes
"Nostalgic animacion" is one (if not the only) episode than it was found. It was uploaded the day 7 of september of 2014, by the user Ausf. D.