It was not easy finding children’s movies that mention menstruation, but Pixar’s Turning Red has saved the day with their becoming of age movie TURNING RED, where they openly and unapologetically discuss period.
One of the books that influenced me the most as a child is Anne of Green Gables. The TV series that’s based on the book has an interesting scene about Anne’s first period. It gives a pick at how menstruation was perceived and handled in the late 19th century.
A Period Piece is a short film about a young girl who is embarrassed by the fact that she got her period. She is most concerned about her borthers' response and tries to hide it from them.