Danica Mae McKellar (born January 3, 1975) is an American actress, mathematics writer, and education advocate. She is best known for playing Winnie Cooper in the television series The Wonder Years.

McKellar has appeared in various television films for the Hallmark Channel. She has also done voice acting, including Frieda Goren in Static Shock, Miss Martian in Young Justice, and Killer Frost in DC Super Hero Girls. In 2015, McKellar joined part of the main cast in the Netflix original series Project Mc2.