The "flower girl" and "page," who pour sake for  guests at a wedding. Nomura, Ehime, 1974.  While, of course, Japanese children in 1974 or today would not dress like this most days, the picture shows two examples of formal wear.  It also provides a visual illustration of a key theme in modern Japanese history -- the combination of "traditions" with "outside influences."  For younger students, it can be fun to compare this picture to pictures of young children participating in wedding ceremonies in other countries.
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Courtesy of Gail Bernstein.