Hayley Kiyoko Alcroft (Japanese: ヘイリー・キヨコ, Hepburn: Heirī Kiyoko Arcroft; born April 3, 1991), known professionally as Hayley Kiyoko, is an American actress, singer-songwriter, musician, and dancer. She is best known for playing Velma Dinkley in Scooby-Doo! The Mystery Begins and Scooby-Doo! Curse of the Lake Monster, as well as Stella Yamada in the Disney Channel film Lemonade Mouth. She recently released her debut solo EP and currently has a recurring role on the ABC Family series, The Fosters.