20+ 100th Day Of School Costume Ideas For All Ages 40 Best old lady costume ideas old lady costume, old women, school dresses Just heard about the Dress Like a 100 Year Old day where elementary school students celebrate their 100 day of school. I found these images seriously disheartening to the point of being sickening, particularly Old Lady Costume for the 100th day of School Crafting with Kids Wearing your white dress with neutrals for women over 50