University of California STEM faculty say test-optional policy has produced severe math readiness gaps, forcing instructors to reteach middle-school math while also covering college-level STEM concepts. A letter signed by more than 600 STEM faculty members calls on UC leaders to reinstate SAT/ACT math requirements for applicants to STEM-intensive majors. Faculty argue that measuring foundational readiness is an equity prerequisite, warning that ignoring preparation gaps does not remove barriers—it moves them into the classroom. They cite UC-San Diego findings that the share of incoming students with below high-school math skills surged dramatically and diagnostic data at UC Berkeley showing recurring severe deficits among early-calculus students. For higher education institutions, the dispute is a direct admissions-policy and student success issue: it affects who can enroll in STEM majors, the structure of bridge remediation, course sequencing, and how institutions design placement and advising. The letter also signals faculty governance pressure in the UC system, where standardized-test policy has previously been a legal and equity flashpoint.