set of back to school a4 posters template in 70s-80s groove style with retro cartoon stationery characters. first day of

back character quote set poster 80s mascot groovy a4 school pencil study education student colorful illustration vector psychedelic hippie text learn lettering knowledge elementary cartoon 90s paper banner vintage summer university template design 1970s triangle science graphic calendar hand retro teacher note background backpack hat graduation 70s book