Democratic presidential candidate Sen. Kamala Harris has proposed a 10-hour day for students to align school with work schedules — a pitch she says is intended to ease the burden on working parents.

The Californian’s plan, introduced Wednesday, would extend the day — though not necessarily classes — in 500 schools nationwide by awarding five-year grants of up to $5 million to elementary schools with a large share of low-income students.

A number of school districts in the Philadelphia region have been moving to change schedules recently. But instead of extending the school day, area districts are shifting it later to help sleep-deprived teenagers.

Under Harris’ plan, schools would work with community partners to develop academic, athletic, or enrichment opportunities for students from “at least” 8 a.m. to 6 p.m. weekdays. Instead of closing for parent-teacher conferences or professional development, schools would be required to provide activities for students.

Given the costs low-income working parents in particular face for child care, Harris described the plan as “an innovative solution that will help reduce the burden of child care on working families. It is time we modernize the school schedule to better meet the needs of our students and their families.”

Teachers and staff would not be required to work longer hours unless they volunteer “and are compensated fairly,” according to the plan, which is backed by the American Federation of Teachers. The federal Department of Education would report on the results in the schools with extended hours after five years, including surveys of parents, students, and staff and “changes in parental employment rates, student performance, and teacher retention” at participating schools.

The idea of a longer school day isn’t new — though it’s generally been pushed as a tool to improve student achievement rather than to alleviate financial stress on families. Districts such as Boston and Chicago have lengthened school days, and a number of charter schools — generally free from teacher-union contracts — have embraced the model.

Harris’ plan — cosponsored by several Democratic senators, including New York’s Kirsten Gillibrand and Ohio’s Sherrod Brown — has a different emphasis. It says caregiving responsibilities cost the U.S. economy $55 billion in lost productivity each year by causing one million women with elementary-school-age children to work less than full time.

The proposal comes as Harris seeks to gain traction in the presidential race. An average of national opinion polls compiled by RealClearPolitics had her stuck in fifth place among Democratic nominees, with about 4% support, through last weekend.