Democratic presidential candidate Sen. Kamala Harris (D-Calif.) introduced a bill Tuesday that would encourage schools to keep schools open three hours longer on weekdays to fit better with parents' work schedules.

"My bill provides 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."

— Harris' statement on the Family Friendly Schools bill

Details: Harris said in a statement the proposed Family Friendly Schools Act would award five-year grants of up to $5 million for schools to "develop high-quality, culturally relevant, linguistically accessible, developmentally appropriate academic, athletic, or enrichment opportunities for students."

The "first-of-its-kind pilot program" is designed to help low-income and working families who can’t afford to pay for child care.

is designed to help low-income and working families who can’t afford to pay for child care. It would give schools resources to stay open during the school year for the entire work day and invest more than $1 billion in "enriching summer learning programs," but it would not force teachers to work longer hours or for less pay, Harris said.

to stay open during the school year for the entire work day and invest more than $1 billion in "enriching summer learning programs," but it would not force teachers to work longer hours or for less pay, Harris said. The bill "does not mandate how schools implement the program so long as they stay open until 6pm," Harris' spokeswoman Meaghan Lynch told Fox News. "Schools have the flexibility to determine what works best for their community, and the students and their families," Lynch said.

The big picture: The average school day begins at approximately 8:10am and lasts for about 6.5 hours, per the National Center for Education Statistics. Less than half of U.S. public elementary schools have no formal after-school program available for students, a 2009 Education Department report shows.

Go deeper: Kamala Harris on the issues, in under 500 words

Editor's note: This story has been updated to clarify that Harris' bill would keep schools open longer, rather than technically extending the mandatory school day.