The retention rate of Hawaii public school teachers after five years of employment stubbornly hovered at just over 50% last school year despite multiple state efforts, including an incentive program for teachers in hard-to-retain categories that has cost $34.5 million so far.

In the 2020-21 school year, just 51% of Hawaii teachers were still employed after five years of work, according to a new report from the state Department of Education released Thursday.

That’s down a notch from the 52% baseline from the 2016-17 school year, set by the DOE’s 2017-2020 Strategic Plan. The goal had been to reach 60% by 2020.

The rate was 54% in the 2017-18 school year, and 51% and 55% in the subsequent years.

Retaining qualified and effective teachers for the long term is important, the report stated, because students benefit from higher- quality education as teachers gain experience and expertise, and because less time and money have to be spent on recruiting new hires.

But Osa Tui Jr., president of the Hawaii State Teachers Association, said he worries that with the unprecedented challenges teachers are facing in the pandemic, retention rates will worsen. “More and more, our students are not going to have access to high-quality educators who are going to stay in the field,” he said.

Relatively low pay in Hawaii remains a large part of the problem, Tui added.

The average Hawaii teacher earned an average of $65,409 in 2020-21, according to the National Education Association. While that was slightly above the national average of $65,090, Tui said the Hawaii teachers’ dollars don’t go nearly as far because of the islands’ sky-high cost of living.

He said local students shrink away from becoming educators when they see their own teachers working multiple jobs to make ends meet. “They ask, ‘Why would I want to do that?’”

In one slice of the DOE’s strategy to solve the state’s chronic teacher hiring and retention shortfall, the department since January 2020 has been paying shortage differentials to teachers in the areas of special education, hard-to-staff geographical locations and Hawaiian language immersion.

Licensed special-education teachers in special- education titled positions have received an annual differential of $10,000.

Teachers in “hard to staff” geographic areas, such as portions of Hawaii island, Maui and Leeward Oahu districts, have received differentials ranging from $3,000 to $8,000. Hawaiian-language immersion teachers have received a differential of $8,000.

The differentials appear to have at least initially improved counts in those specific shortage categories. For example, the DOE said there was a 16% increase in the number of licensed special-education teachers; a 45% decrease in the number of nonlicensed special- education teachers; and a 43% decrease in the number of special-education teacher position vacancies.

The $34.5 million price tag for the differentials could rise to $37 million if all positions are filled, interim state schools Superintendent Keith Hayashi told the state school board Thursday.

While the differential program needs more data over time to prove its long-term effectiveness, and DOE officials said more work remains to improve overall retention rates for all types of teachers, Hayashi said, “It is clear that the teacher differentials have a positive impact on the number of licensed qualified teachers” in those categories.