Summary:
Zip code 95391 has seven K–8 schools in Mountain House, all part of Lammersville Joint Unified. Their 2025–2026 average proficiency was 77% in English language arts (ELA), 73% in mathematics, and 70% in science—about 27, 34, and 34 percentage points above California, respectively. Every school exceeded the state result in all three subjects, but the differences between local schools are substantial: the strongest-to-weakest gaps were 22 points in ELA, 33 in mathematics, and 25 in science. The area-wide averages therefore do not tell parents how widely results vary from one school to another.
Julius Cordes Elementary leads in ELA at 88% and mathematics at 89%; its ELA result is 11 points above the district, and its mathematics result is 18 points above. Hansen Elementary leads in science at 82%, less than 1 point ahead of Evelyn Costa Elementary. Costa also scores strongly, at 84% in both ELA and mathematics. At the other end, Wicklund Elementary is lowest in each subject: 66% in ELA, 56% in mathematics, and 57% in science. Even so, those results are 16, 18, and 21 points above the state, respectively.
Across the two years provided, the seven-school averages rose 1 point in ELA and 3 points in science, while mathematics fell 1 point; the group’s advantage over the state narrowed slightly overall. SchoolDigger ranks Cordes 51st of 5,804 schools and Costa 232nd; both improved their ranks over the three years shown. School measures add context but do not neatly match performance: for 2024–2025, free/reduced lunch eligible shares ranged from 3% to 18%, averaging 10%, while student-teacher ratios averaged 23.4:1. Cordes had the group’s highest ratio, 25.3:1, while Wicklund had the lowest, 22.0:1; in 2025–2026, chronic absenteeism was 4% at Cordes and 12% at Wicklund.
Thank you for your feedback!