School districts are coming back to property owners for another nine-figure bond, and once again the pitch is "aging infrastructure" — this time $321 million from homeowners in the Los Gatos-Saratoga Union High School District, on top of the $99 million they already approved in 2014.

Measure N on the November ballot would raise property taxes by $30 per $100,000 of assessed value and take 14 years to pay off — before interest. Superintendent Heath Rocha says the money goes toward deteriorating roofs, restrooms, electrical and HVAC systems, plus modernized cafeterias and classrooms. "We've been good fiscal stewards but we have aging facilities," Rocha told the Mercury News. "Our facilities need to match the performance and achievement of our students."

But the project list tells a fuller story than leaky pipes. Los Gatos High would get a new parking structure expanding capacity from 337 spaces to nearly 600, a new field house with fitness center and PE classrooms, and an upgraded 70-year-old career technical education building. Saratoga High would get new math classrooms, a dedicated robotics building with competition fields, and a drop-off zone reconfiguration. Both schools get cafeteria and security upgrades.

That's a lot more than emergency maintenance. It's campus expansion dressed up as necessity.

The district's last bond, Measure E, passed in 2014 and raised $99 million for modernization. Rocha noted the original tax rate was projected at $18 per $100,000 of assessed value but dropped to $13.20 after refinancing — saving property owners $3.6 million, he said. The district now boasts the lowest K-12 bond tax rate among 30 districts in Santa Clara County.

Lowest rate, maybe. But the question working families should be asking: where did that $99 million go, and why is another $321 million needed barely a decade later? If roofs and HVAC systems are still deteriorating after nearly $100 million in bond spending, what exactly was fixed?

Silicon Valley Taxpayers Association President Mark W.A. Hinkle pushed back, arguing facility upgrades don't improve academic outcomes. He said needed funds should come from the annual operating budget, not another ask of taxpayers. "What they should do is decide what's the priority," Hinkle said. "If (they) need to hire more qualified teachers because the academics are so poor, buying new technology or putting a new roof on the building (is) not going to get you what you need."

Hinkle has a point. The district insists an independent citizens oversight committee and mandatory audits will guard the money. But oversight committees don't set priorities — bureaucrats do. And the pattern is clear: pass a bond, spend it, come back for more.

Four of the five outlets covering this region this week had nothing to say about any of it — they were running high school football scoreboards. Only the Mercury News reported on the bond measure at all. That's how these things slip through: nobody's watching the money until the tax bill arrives.

The district says projects were "prioritized based on community input." Whether that community includes the property owners writing the checks — or just the people spending them — is the open question.