Charter schools represent an example of an improvement that is trickier to manage than it sounds. In theory, few would dispute the contention that independent schools with a distinct mission, untethered from an educational bureaucracy, can operate more freely and produce the thing that’s too often missing in public education: innovation.

Last week’s series by Star-Advertiser writer Susan Essoyan chronicled a few of the clear success stories: Ka Waihona o ka Naauao in Nanakuli, Hawaii Technology Academy in Waipahu, Kualapuu School on Molokai. Some schools, even in areas of socioeconomic distress where academic success has been elusive, are showing progress.

However, Hawaii’s 10-year-old charter schools venture undeniably has fallen short of its full potential. There are several weak links:

>> Charter schools receive taxpayer funds, but not as much as the conventional public schools do. Money in the federal stimulus bill helped some of them through the strain of the recession, but that money’s essentially spent now, and it’s not coming back.

>> Some of those limited funds must be spent on renting a facility, which administrators of traditional public schools can cross off their worry list.

>> Each of the schools is run by a volunteer board. While most are clearly dedicated individuals, few have training in what the job entails. That’s how gaps in fiduciary oversight — including the one leading to the staff nepotism controversy at Myron B. Thompson Academy — open up.

>> The Charter Schools Review Panel, established in 2007 to approve new schools and review existing ones, oversees all 31 charters. That’s simply too much for a single board, itself consisting entirely of volunteers, to handle. Most charter-authorizing agencies in districts across the mainland manage a load closer to a half-dozen. The review panel needs to take care not to add to its outsized burden with too many new charters before the roster has been trimmed somewhat.

Some charter schools, like experiments in the lab, are bound to fail. But after a decade, not a single charter has been withdrawn. Judging by the lackluster and even dismal academic achievement records at some of the schools, at least some weeding should have been done by now. The students at those sub-par schools over the years of inaction have now missed their chance at a decent public education.

Finally, this inertia may be at an end. The missing piece that prevented school closures in the past — administrative rules governing the ending of school charters — has been supplied, and decisions on the first round of schools up for review are pending.

The Legislature has taken a stab at tightening up the accountability gap with the passage of Senate Bill 1174, still awaiting the governor’s signature. It would put charter schools on a six-year calendar of review and reauthorization and require local school boards to adopt an ethics policy.

It also would establish a task force on charter school governance, accountability and authority. This may be useful as a start, because one of the other major deficits — a shortfall in resources, both for school operations and training of boards — will be hard to erase until the economy recovers more fully.

Unfortunately, the Legislature failed to provide another fairly low-cost improvement: liberalizing the state charter schools law so that more than one agency can authorize and review charters. That door shouldn’t be thrown wide open, but certainly a few credentialed educational entities, such as the University of Hawaii College of Education and Kamehameha Schools (which is already injecting funds in Hawaiian-focused charter schools) should qualify as authorizing agencies.

Maintaining the effectiveness of charter schools without quashing their innovative character is a delicate balancing act. But if the state takes additional steps to provide support to properly supervised schools, the result should be taxpayer money more wisely spent, reinforcing the schools that are actually getting the job done for our kids.