Since you mentioned CalPoly as a school she is considering I’m guessing she is a CA resident. If she decides Physics is what she wants to do then be sure she takes a look at the Physics major offered by the UCSB College of Creative Studies (Physics | UCSB College of Creative Studies) CCS is sometimes called grad school for undergrad since they have small lower-division classes and students can skip intro classes and sign up for literally any class at UCSB, undergrad or grad, that they and their advisor think they are ready to take.
UCSB is also home to the Kavli Institute For Theoretical Physics What is the Kavli Institute for Theoretical Physics? | KITP