Any family looking to move into a neighborhood with good schools knows the magic "800" number.

Few would be able to explain it, but California's Academic Performance Index, in place since 1999, uses student results on the California Standards Tests and other indicators to score schools on a 200-to-1,000 scale. The target for all schools is 800.

But that index has basic flaws. Knowing that a school has an API of 820, pretty good, tells nothing about whole groups of students who are not on grade-level in reading and math. As critics point out, such a school has little incentive to pay attention to struggling students, so long as enough high-performing students keep the score above 800.

Further, struggling schools scoring below 800 are given annual growth targets so small that it would take decades – if not generations – to reach the 800 goal.

At the other extreme, the federal No Child Left Behind Act of 2001 set a target that all students – yes, 100 percent – must be on grade level in reading and math by 2014.

The one sets progress targets too low; the other shoots for the moon.

Fortunately, setting high but achievable goals is possible.

On the federal level, the Obama administration has announced that while Congress works on reauthorizing No Child Left Behind, states may apply for waivers from the 2014 targets – so long as they build an accountability system that sets ambitious but achievable goals, measures progress in improving academic achievement for all students and takes real action to turn around persistently low-performing schools. California should apply.

At the state level, the Legislature has passed a bill by Senate President Pro Tem Darrell Steinberg (Senate Bill 547) that would set up a process to overhaul the Academic Performance Index. Gov. Jerry Brown should sign it.

For years, California has been demanding flexibility. Well, now we've got it. Let's use the opportunity to rethink how we're using billions of state and federal dollars to improve our public schools.

Under Steinberg's bill, a broad-based committee would begin meeting in January to develop a new Education Quality Index, which would have to be approved by the State Board of Education by August 2014 and take effect that fall.

The new index would still include standardized tests. Having an objective measure of how much students know at each grade level remains extremely important. But it would add dropout and graduation rates, as well as measure student readiness for college and careers.

A key task would be to set high, clear, achievable progress targets not just schoolwide, but for all groups of students within a school – and act aggressively to turn around the lowest performing schools. That is where California's existing accountability system is weakest.

Brown has until Oct. 9 to sign SB 547 and Oct. 12 to decide whether to apply for a federal waiver. If he does nothing, California will bump along with the flawed API and impossible NCLB targets, spending dollars in crazy ways.

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