Traditionally, homework has been used as a vehicle for students to practice skills and build on what they’ve learned.

That model is increasingly being questioned, though.

And a growing number of Hawaii teachers are instead "flipping" their classrooms — introducing material through digital mini-lessons assigned for homework, then having students apply and expand on what they learned during the school day.

Josh Winter, who teaches social studies and English at St. Andrew’s Priory School, flipped his sixth-grade classes last school year and said the model allows teachers to cut down on lecturing and focus on discussions, projects and individualized tutoring.

The approach also appeals to tech-savvy students, he said, because the revamped homework lessons often come in the form of videos, narrated computer slideshows or online tutorials.

"If the instruction is delivered at home, the in-class lecture changes dramatically," Winter said at a recent talk for teachers on the model. "It changes the entire dynamics of the class."

The model has its critics. Some say lecturing is ineffective, whether delivered online or in person, and that students aren’t likely to learn much from their homework tutorials. Others say the model relies too heavily on technology, leaving students without home access to computers and the Web behind.

Still, the "flipped classroom" is increasingly being seen in Hawaii classrooms. Schools trying it include Sacred Hearts Academy, Punahou School, Kapolei High and Wheeler Middle.

At Punahou last week, about 20 teachers gathered for a discussion on the model with Winter and Yasmin Saban, who teaches math at Priory. The two also led a two-week training on the model, as part of Punahou’s summer Lab School for teachers.

Saban said flipping a classroom requires teachers to move away from the "sage on the stage" way of presenting lessons and instead become a facilitator, a tutor and a mentor.

"You have to give up a lot of the power," Saban said to teachers at the Punahou presentation. "You have to give students the freedom to navigate through it on their own."

Saban’s homework for students consists of computer slideshows, in which she presents formulas and solves problems step by step. Once back in class, Saban "jumps into the good stuff." Through class discussions and group work, she said, students make their way through problems together.

The homework instruction "is supposed to be their first glimpse" of the material, she said. "It’s kind of an introduction."

The in-class work, she said, is vital to ensuring students understand the content and can apply it. She said by working through math together, students who may have become frustrated and quit can instead seek out help from her. And students excelling in class can jump ahead or tutor others.

At Wheeler Middle in the upcoming school year, all seventh-grade teachers will adopt a version of the "flipped classroom" by emphasizing project-based learning during the school day.

Luis Oros, a Wheeler Middle math teacher who piloted the model in his class at the tail end of last school year, said a grant enabled the school to buy iPads for all seventh-graders.

The iPads, which will have to stay at school, will have the instructional materials students need as they work through units.

In Oros’ class, students work in teams through three steps. First, they put the definitions of math terms in their own words. Then, they watch video tutorials of how those math concepts work and complete straightforward questions. Finally, they complete math projects, applying what they learned.

At home, students are able to access all the instructional materials on the Web so that teams can work at their own pace.

"At no point throughout the unit am I lecturing," Oros said.

Instead, Oros circulates, helping struggling teams, asking students to explain their thinking and keeping them on task.

Oros said he tried the model because many students in his class weren’t engaged. He said when he would lecture, there were students who didn’t understand the lessons, students who appeared bored and students who listened intently.

In his second year of teaching, Oros said, he would put his notes on a projector, go through them page by page to teach a concept and have students take notes.

"It was horrible," he said.

When he tried the flipped model, he saw results — both in student engagement and in test scores. A big boost in how his kids performed persuaded Wheeler to take the model grade-wide.

Oros said while the flipped model is no cure-all, it’s a considerable improvement to how he had been presenting new material.

"The era of lecturing is over," he said.

Merry Ifuku, who teaches accounting at Kapolei High, plans to flip some of her lessons in the coming school year. She said other teachers in Kapolei’s business academy are also trying the model.

Ifuku attended the Punahou training last week, and said previously she has discussed new material in class, then worked through some problems with her students and assigned more problems for homework. But she said her students were struggling with the homework and growing frustrated.

"The whole concept of flipping is worth trying," she said. "This is my first endeavor. It’s kind of overwhelming."

Ifuku added she’s still trying to figure out how she’ll help students who don’t have access to the Internet at home.

She said she might invite them to complete their homework at school.