The U.S. is facing a shortage of teachers in its K-12 schools, and the situation doesn't seem to be improving much.

Teacher shortages across many districts became a hot topic in 2015, and a new study from the Learning Policy Institute details the causes of the shortage — primarily, teachers leaving the profession and fewer studying to become educators in the first place.

The study finds that between 2009 and 2014, teacher education program enrollments dropped from 691,000 to 451,000 a 35 percent reduction.

Additionally, U.S. teachers are leaving the profession at high rates hovering around 8 percent over the last 10 years. Compare that to other high-achieving regions like Finland, Singapore and Ontario, Canada, where attrition rates are 3 to 4 percent.

The teacher shortage first began about six to eight years ago with the start of baby boomer retirements, said Anne Udall, executive vice president of program strategy at New Teacher Center (NTC), a nonprofit that aims to improve teacher effectiveness.

"That was one of the major factors that led to a teacher shortage, along with changing economics and changing opportunities for people coming into the workforce," Udall told MultiBriefs Exclusive.

More than 50 percent of teachers in high-need districts leave within five years, according to data compiled by NTC.

"People leave because they feel very overwhelmed; they don't feel supported by their administrators," Udall said. "The working conditions are very tough."

The Learning Policy Institute study agrees, finding that administrative support or lack thereof is the most common reason teachers decide to stay in or leave a school. Other factors affecting teachers' decisions to leave include professional learning opportunities, instructional leadership, time for collaboration and planning, colleague relationships and decision-making input.

Additionally, salaries may play a part in the decline, Udall said. She believes creating equity in education could help retain more teachers, and it starts with paying teachers better salaries.

"It's about priorities in our communities," she said. "If we can spend a lot of money building football stadiums, we should be able to afford working salaries for teachers."

And not all school districts are funded the same way. More than a quarter of states provide less money to schools with higher concentrations of students from low-income families, according to NTC. That gives higher-quality teachers incentive to work in wealthy districts, resulting in less prepared teachers in lower income districts, Udall said.

Another way to boost teacher retention rates? Give each new teacher a mentor or coach, Udall said. This is especially helpful for new teachers, since the learning curve can be steep from day one in the classroom.

"Teaching is one of the few professions I know of where you are supposed to be as good on your first day as you are on your last," she said. "The day-to-day management and expectations can be overwhelming."

NTC has implemented its own two-year mentoring program in districts in 38 states across the country.

Udall also recommends mapping clear career paths for teachers. For example, give educators options outside the classroom within their profession, whether that's becoming a mentor or curriculum specialist, or having some other form of mixed teaching options.

For now, though, the numbers still stand: 250,000 to 300,000 new teachers are needed in the U.S. every year, and we may not be able to overhaul the shortage right away, Udall said.

"If we continue to put the kind of attention on it that it needs, we will continue to improve," she said. "We need to make sure once teachers are in, they stay in. That is a really important piece of the puzzle."