In a state that's always looking for ways to improve its public education system, a new national study released last week by a nonpartisan think tank is worth noting.

That report by Education Sector revealed that more half — 55 percent — of teachers surveyed said it's far too difficult and too time-consuming to get rid of ineffective teachers, with half citing union intervention as an obstacle. And 49 percent said they personally know "ineffective" teachers in the classroom.

The study holds a few lessons for Hawai'i.

Improving the teacher evaluation process is a solid place to start.

Indeed, the survey found only 26 percent of teachers felt their own evaluations were useful and effective, with 79 percent saying the process should be strengthened to prevent weak teachers from becoming "too entrenched" in the system, making it all the more difficult to remove them.

Says Hawai'i State Teachers Association President Roger Takabayashi: "The study is right on. Teachers agree, bad teachers give us all a bad name.

"All parties agree, the evaluation process needs work. Improving instruction is the bottom line of any teacher evaluation process. The difficulty is how do you measure that?"

That's a key point.

It's true that student achievement should not be the sole indicator of a teacher's success. Many variables — socioeconomics, family situations and language barriers among them — play a key role in how well a child performs in school.

Unlike private schools that have the luxury of being selective when it comes to students, public schools have the mission of educating all students, including those with special needs. So finding a common denominator for instruction becomes all the more difficult.

But while it should not be easy to summarily dismiss a teacher who may be at the receiving end of an angry parent's complaint, for instance, there should be a sensible process for ensuring the quality of classroom instruction.

From the start, teachers need a clear understanding of what those expectations are, including sensible benchmarks that show when and how those standards are achieved.

Streamlining the process for removing teachers who fail to make the grade is essential. The longer an ineffective teacher is kept on, the more students are adversely affected by poor instruction. That's something they'll carry with them well beyond that grade level or subject — and they deserve better.

So it's encouraging to see the HSTA and the DOE working on that process.

"We both recognize the need, if need be, to remove teachers who are ineffective or less than satisfactory. So this dialogue is taking place; and this is something that has not happened in the past," said Leighton Hirai, the state's personnel specialist.

Next point: The frequency of teacher evaluations should increase. Currently, teachers are evaluated roughly every five years; probationary, or new teachers, within two years.

Increasing the frequency of evaluations to at least once every two years for tenured teachers, and within a year for new teachers, would provide a more sensible time frame — not just to weed out chronic underperformers, but also to provide the right support for teachers who need extra help. DOE officials said they are working with HSTA on creating a more frequent schedule.

A sensible path to help struggling teachers improve is also key. That path should include more mentoring of inexperienced teachers, and additional options for classroom management strategies that provide a game plan for teachers who need the extra help.

More should be done to ensure teachers and administrators alike are aware of what programs and resources are available to them.

Teachers have a unique oppportunity to impact the lives of our students — that's an important role.

Providing the right framework for evaluating teachers — including providing the support needed to improve their skills and having a sensible and timely way to remove ineffective teachers — is a smart investment we can make now that is sure to yield big returns for Hawai'i's students and our future.