Allotting bonus money to reward exceptionally effective school principals is a worthy program to test in Hawaii schools, so it’s encouraging to see a commitment to such an experiment from both the state Department of Education and the principals’ union.

It is by no means a silver bullet. Current research does not support the notion that a bonus alone is enough to improve student achievement, which has to be the bottom-line goal of any educational system.

However, assuming the bar is set high for such merit payments, it should be part of the professional supports put in place as a part of school reform.

A basic agreement between the DOE and the Hawaii Government Employees Association was reached in April for a pilot program that will involve about 82 schools, making each qualified principal eligible for a one-time, $10,000 bonus, based on their employee evaluation.

The precise qualifications are still under discussion, according to the DOE, but the memorandum of understanding spells out the basic percentages. For the coming pilot program, effective in the 2012-2013 school year, 40 percent of the evaluation score would be linked to growth in achievement by students in their schools. The "intent," according to the memoran- dum, is that the student-achievement portion of the score will rise to 50 percent when the program is rolled out to all principals the following school year.

The money for bonuses will come, at least initially, from Title II, a category of federal education funds set aside for purposes such as professional development for educators, compensation for teacher mentoring services and help for teachers in gaining the highly qualified-teacher status, said department spokeswoman Sandy Goya.

How many principal bonuses will go out is unknown, but what is clear is that some of these funds must be reserved to incentivize teachers as well. In either case, the bonuses should be for achievement well above the status quo, rewarding real excellence rather than mere competence, with the primary focus on raising student performance.

The teachers union, the Hawaii State Teachers Association, declined specific comment on the principals pending a deal or its own negotiations on linking teacher evaluations to student academic growth. HSTA President Wil Okabe would say only that "we look forward to working with all the major stakeholders on ways to raise student achievement."

Despite a growing popularity nationwide for merit pay, the link with academic results is not proven. A 2011 study by the RAND Corporation of a program in New York City compared performance of about 200 participating schools with controls, and found no correlation between the bonuses and student achievement. The city, beset by financial problems, cut the program altogether.

That said, the Obama administration still seems bullish on the concept, especially if it’s paired with other supports. For example, administration alumnus Rahm Emanuel, now mayor of Chicago, has launched a principals’ merit-pay program in his city. It’s financed by charitable donations, an approach Hawaii might consider, at least on a supplementary basis, if the pilot program works here.

The key is to make it part of a menu that also includes training, mentoring and recruitment of the right principals for the right schools, Emanuel rightly observed.

Critics say that educators are not motivated by financial concerns alone. Maybe so, but policymakers should note that the most successful public school systems around the globe, such as that of Singapore, have elevated the stature of the profession and pay their teachers and principals well.

Overall enhancement of the profession should be Hawaii’s end goal as well. And a well-designed program of rewards for boosting student achievement represents a step in the right direction.