Black Diamond Middle

Located at 4730 Sterling Hill Dr., in Antioch, California, Black Diamond Middle is a low-enrollment middle-grades school that educates 358 students (grades 7 through 8), overseen by Antioch Unified. That puts it 46% below the typical public school in California, which averages around 659 students.

Antioch Unified runs 25 schools in total, collectively educating 15,111 students. Black Diamond Middle is one of those campuses.

In terms of who attends, Black Diamond Middle lists that the most-represented group is Hispanic (42%), with the rest of the student body spread across multiple groups. The remainder is composed of 33% Black, 9% Asian, 8% White, 6% multiracial. By comparison, Contra Costa County as a whole is about 28% Hispanic, so the school skews visibly more Hispanic than its surroundings.

In terms of school funding signals, Staff filings list 17 full-time-equivalent teachers, which works out to roughly 21.3:1 students per teacher. That tracks the state average closely. About 81% of enrolled students meet the income threshold for free or reduced-price lunch, often used as a Title I proxy. That share is higher than Contra Costa County's rate of about 45%.

On a residual basis (actual vs predicted given the student mix), Black Diamond Middle tracks the demographic baseline. The model predicts 31.2% given the school's FRL share; actual proficiency is 17.7%.

Across the wider county, Contra Costa County reports that median household income runs about $127,229, roughly 45% of adults have completed at least a four-year degree, and roughly 6% of residents live below the federal poverty line. In all, Contra Costa County runs 280 public schools (combined enrollment of about 167,423 students), of which Black Diamond Middle is one.

Thomas Gaines Virtual Academy is the nearest neighboring public school, about 0.0 miles from this campus. 8 of the 8 nearest public schools sit inside a five-mile radius. Ranking that nearby cluster on reported proficiency puts Black Diamond Middle at 7th of 7; the average score across the group is 23.7%.

The campus sits in a commuter-belt setting.

Over the past 7-year window. Over the past 7-year window, the student count ticked down 4%: 374 students in 2018 compared to 358 in 2025. The Hispanic share of enrollment rose from 36% to 42% over that span. Class-load math has pulled in: from 23.7:1 in 2018 to 21.3:1 in 2025.

On this page, members of the Black Diamond Middle community share and discuss open house dates, ride-share offers, and field-trip permission slips. Contributors range from current parents to recent graduates and teachers.