Local teens will soon be working harder for their high school diplomas.

Last week the Napa Valley Unified School District board of trustees approved the College and Career Readiness Initiative, designed to increase academic rigor for students from kindergarten through the 12th grade.

The initiative requires high school students to take courses in line with University of California and state university entry requirements. District officials say it also helps prepare non-college-bound students for future careers.

Some local teachers have voiced concern that the new requirements will cut down on students’ opportunities to take elective courses, as well as occupational and career technical classes. Today, high school students take between 75 and 80 units of elective courses, but the measure allows for just 45 elective units for Napa High School students and 50 units for those at Vintage High.

Over time, the plan will change graduation requirements by mandating three years of math instead of two and adding a lab class as part of students’ required two years of science work.

Finally, the plan calls for a year of visual and performing arts education, as well as two years of foreign language study. Current requirements give students a choice between either one year of foreign language or one year of visual and performing arts course work.

At a recent school board meeting, Frank Varni, a social studies teacher at Vintage High School, told trustees that more students should have more access to the core courses required for the changing graduation demands.

Switching students from a six to a seven-period day would help time-challenged teens meet requirements, he said, but making the move would require teachers to work longer days. The change would likely rack up costs for the cash-strapped district.

Mark Morrison, the district’s director of secondary curriculum and instruction, said although the district is not considering a seven-period day, students could lean on extra class periods — known as “early flight” and “late flight” courses — to accommodate growing schedules.

Teachers and district officials agree that the plan requires more student intervention and tutoring services. But Morrison said that over the long haul, raising standards at all grade levels should cut down on students’ needs for extra help.

District officials are also working out the details of a plan to allow students unable to complete the required coursework — even after making extracurricular efforts to do so — to earn a diploma.

Cindy Watter, a Napa High School English teacher, told trustees that students will need more high school counselors on staff to help them navigate changing schedule requirements.

The push for higher standards and concern about resources for students come as the district grapples with more than $10 million in state cuts and an expectation that budgets will remain tight for at least several years.

“It’s not going to be cheap,” Watter said, adding, “As it is right now, our counselors are completely overwhelmed.”

Next year’s ninth-graders will be the first affected by the initial phase of graduation requirement changes and must take one year of visual and performing arts courses. Today’s sixth-graders — who will be the class of 2016 — are slated to be the first students to complete all new graduation requirements.

The district will be tracking dropout rates and other data as the plan unfolds, Morrison said.