Why Counting Petaluma's School Districts Is Harder Than It Should Be

Quick question: how many public school districts serve Petaluma?
I tried to answer this cleanly and couldn't. The City of Petaluma's website counts 13. Wikipedia and the county's school listings point to nine or ten, depending on how you count. The number changes with the source and the definition. That turned out to be interesting to me, and it shifted my focus. This post is about why a city of 60,000 has so many districts, why the count depends on how you define one, and what it means in practice.
First, why so many at all?
Petaluma didn't design it this way. The system was drawn a century ago, when each ranching community had its own schoolhouse, and it has never been fully consolidated since.
In the early 1900s, Sonoma County had around 100 school districts, most of them single-classroom schoolhouses serving families within a few miles of one another. Consolidation began when cars and school buses made it possible to move children longer distances. By the mid-20th century, the county had dropped to about 40 districts, roughly where it sits today. That's still one of the higher district counts in the state.
A 2011 Sonoma County Grand Jury report looked at this fragmentation. It found that twelve county districts operated just one school, and it commended Petaluma for taking "bold first steps on the road to consolidation/unification." Those steps didn't lead to full mergers, but they weren't nothing, and I'll come back to that.
Why the count is difficult to determine:
Several things make a clean count difficult.
Start with Petaluma City Schools. It's legally two districts, Petaluma City Elementary and Petaluma Joint Union High, that share a single board and operate as one unit. Count it as one or two, and your total shifts before you've even left downtown.
Then there are the smaller districts around the city: Old Adobe, Waugh, Wilmar, Liberty, Cinnabar, Dunham, Two Rock, and Laguna Joint. That's eight more, several of them a single school serving rural families.
Depending on how you count PCS, and whether you fold in charter schools that carry their own governance, you can reasonably land anywhere from nine to 13. None of those numbers is wrong. They're just counting different things. The takeaway isn't the exact figure. It's that even a careful resident, trying in good faith, can't easily produce one, because the system genuinely is that layered.
The districts, as best I can list them:
Here's what serves Petaluma and the surrounding area. Enrollment figures are labeled with the year of the source; the smallest districts I could only find older or approximate numbers for, and those are marked.
Petaluma City Schools (K-12, covers most of the city plus rural south): about 7,500 students (2024-25). Legally two districts, elementary and high, under one board.
Old Adobe Union (K-6, east side, within city limits): 1,881 students (2024-25).
Waugh (K-6, east side, within city limits): 790 students (2024-25).
Wilmar Union (K-6, rural): 236 students (2024-25).
Liberty (K-6, rural, west): 212 students (2023-24).
Cinnabar (K-8, rural, west): around 200 students (approximate).
Dunham (K-6, rural, west): under 200 students (approximate).
Two Rock Union (K-6, rural, west): around 130 students (approximate).
Laguna Joint (K-6, rural, straddles the Sonoma and Marin county line): very small, under 25 students (sources range from 9 to 21).
All of the elementary districts feed into the Petaluma Joint Union High School District for grades 7-12, which shares a board with Petaluma City Schools. Several charter schools operate on top of these, some with their own governance, which adds to the count.
The part people miss: some services are already shared
Here's the nuance the raw count leaves out. Several of the small districts pool administrative services through a South County Consortium hosted by Petaluma City Schools. Its member list includes Cinnabar, Waugh, Wilmar, Dunham, Two Rock, Liberty, and Old Adobe, alongside Petaluma City Schools itself.
You can see the sharing in the leadership titles too. Old Adobe's leader carries a "Co-Superintendent" title. Cinnabar's is a "Superintendent/Principal," one person doing two jobs. So a raw count of "one superintendent per district" overstates it. Some of those roles are combined or coordinated through the consortium.
I couldn't confirm exactly which functions the consortium centralizes (business services, payroll, HR, and special education support are the usual candidates), so I won't claim more than the structure itself. But it's fair to say these districts are more connected behind the scenes than the map suggests. This looks like what the Grand Jury's "bold first steps" actually became: shared administration rather than full mergers.
What does this mean for families?
A few things are clear even with the gaps above.
Enrollment. Where you live determines your default K-6 district. There's no single citywide attendance map for the elementary years. Two families a short distance apart can be in different districts, with different schools, budgets, and cultures. At 7th grade, many students converge into Petaluma Joint Union High, with the rest in charter or private schools.
Voting. You vote for the board of the one district you live in. Your vote shapes your local schools, not your neighbor's, even if they're close by.
Cost. Running multiple districts carries administrative overhead, which is what the Grand Jury flagged. The consortium appears to reduce some of that duplication, though I can't put a dollar figure on it. Whether the current setup strikes the right balance between efficiency and local control is a genuine open question, and one that's been raised more than once without a full resolution.
To find your district:
Use the county's district lookup tool to see which K-6 district you're in based on your address.
One more thing
I did my best to get this right, but this is a genuinely complex topic, and some of my numbers are approximate or from older sources. If you have additional information to share about any of the districts, I'd love to hear it. Drop a comment below or send me Porchmail. 💌

