Cherry blossom is a classic symbol of Japanese elementary school uniform buttons.
The photos of Japanese national school uniform (国民学校の学童服) in ramie fabric material, circa 1941-1947 with the wood buttons, is kindly shared by the Shishu Center of War-Time Historical Records (信州戦争資料センター) .
During WWII, when scrap metal was in short supply, buttons were made with materials such as wood or ceramic.
National School Uniform, 1941-1945, copyright 信州戦争資料センター. All rights reserved.
Close up with buttons, National School Uniform, 1941-1945, Copyright 信州戦争資料センター. All rights reserved.