More than 600 UC STEM faculty members warned that test-optional admissions have produced severe math under-preparedness for incoming students, prompting a call to reinstate SAT/ACT math requirements for STEM-intensive majors. They describe widening preparation gaps serious enough that faculty across the University of California system must reteach middle-school math while simultaneously delivering college-level STEM instruction. The faculty letter points to evidence from UC San Diego diagnostic findings showing a dramatic increase in students arriving below high-school math level, including a large share below middle-school level. UC Berkeley’s internal calculus diagnostics are cited as showing recurring severe deficits. The faculty appeal reframes admissions measurement as equity: they argue that ignoring readiness just shifts barriers into the classroom where remediation is harder and more costly for the most vulnerable students.