The project, which is being developed by Bee Movie writer Spike Feresten and comedian Louis CK, focuses on a group of young people trying to achieve their dreams despite the difficult economic climate.
Tisdale has now joined the cast and will play Petra, Deadline reports.
Petra, who works as an assistant to a vintage clothing designer, is described as attractive and sarcastic.
Tisdale is possibly best known for her role in the High School Musical movies. Since then, she has appeared in The CW's drama Hellcats and recently had a guest role in Raising Hope.
Other comedy pilots in the works at CBS include Partners, which stars Ugly Betty's Michael Urie and One Tree Hill's Sophia Bush, and a project from Bridesmaids star Melissa McCarthy.