Project Kids members, Berryz Kobo and ZYX.

She was cast as one of the main characters in "Koinu Dan no Monogatari".

In 2003, Shimizu was chosen to join the group ZYX, which consisted of five Hello!

They remained active until 2004, when Saki and Momoko Tsugunaga became members of Berryz Kobo.

Project participated in a large shuffle group that produced the single, "All For One & One For All!"

On December 31, 2006, Shimizu took the stage at the 57th edition of Kōhaku Uta Gassen as a backup dancer in Morning Musume's performance of Aruiteru, along with the remaining members of Berryz Kobo, Country Musume and Cute.