Philly’s got the worst school librarian ratio in the U.S. This group is protesting.

Kayla Johnson is a library kid — the kind who gobbles up books and relishes time spent in the stacks of her school library and interacting with the librarian at the Masterman School.

But Johnson, a senior at the elite Philadelphia magnet school, knows how privileged she is. Just seven certified school librarians are left in the city’s public schools, according to the Pennsylvania School Librarians Association.

Libraries, Johnson said, are a “simple necessity, a fundamental basic.”

To underscore that statement, Johnson and 150 others gathered on the steps of the Philadelphia School District’s headquarters Friday to rally for school libraries and certified school librarians.

State Rep. Thomas Murt (R., Montgomery County), a former teacher, is a cosponsor of legislation that would require every school in Pennsylvania to have a certified librarian. Research shows that students with access to certified school librarians perform better, especially in low-income areas.

“Why do the students in Philadelphia not have that opportunity? To me, that sounds like discrimination,” said Murt, whose district includes part of Northeast Philadelphia.

Nationwide, 91% of schools have school libraries, but just 61% have certified school librarians, according to the American Library Association.

Philadelphia’s public school system once employed certified librarians in almost all of its 200-plus schools. Today fewer than 10 certified librarians are on the district payroll, with about a dozen more schools able to keep libraries open at least part-time with volunteer staff.

It mirrors a national trend: When budgets get tight, librarians often get cut, with administrators saying that in an increasingly digital world, children can access resources online in lieu of working with a librarian.

» READ MORE: Philadelphia school librarians: a species nearly extinct?

Murt said that is a poor choice.

“Just because there’s calculators, we don’t do away with math teachers,” Murt said.

The school district in the past has said principals remain free to hire librarians if they choose to prioritize them, but most principals say their budgets are stretched too thin.

Megan Lello, a district spokesperson, said Friday that the district provides classroom libraries and other media and technology to support the literacy aim that has been a hallmark of Superintendent William R. Hite Jr.'s administration: making sure all children read on grade level by age 8.

“The school district values the expertise of any staff member working to enhance the literacy skills of our students,” Lello said in a statement. “The collective work to help students read on or above grade level is important to ensure the next generation of this city’s leaders are thoughtful and competent citizens.”

Cathi Fuhrman, president of the Pennsylvania Association of School Librarians, which organized the rally with EveryLibrary, a national nonprofit political action committee, said the nation’s eyes are on Philadelphia.

“The School District of Philadelphia has the worst ratio in the entire nation of certified school librarians,” Fuhrman said.

Pennsylvania mandates a library and librarian in every state prison, said Jerry Jordan, president of the Philadelphia Federation of Teachers. Not doing so in every school sends the wrong message, he said.

“It’s disgraceful,” Jordan said.

» READ MORE: Read more: A look inside one suburban private school's new library

Deborah Grill, a retired Philadelphia educator, began her career when the district employed close to 200 school librarians, and she worked in that position until 2005, when her position was cut.

She became a reading coach and, when a community group wanted to identify student priorities for potentially reopening the school library, Grill accompanied Germantown High students to the cutting-edge library in Springfield Township, Montgomery County.

Grill vividly remembers what one of her students told her at the end of the visit.

“‘I will never be able to compete with these students when I go to college,’” Grill remembers the young man saying.

Philadelphia student Rory MacDonald has seen the disparities.

MacDonald attended Dobson Elementary, in Manayunk, in his early school years. It had no library. Now, he goes to Masterman, with its bustling library and veteran librarian. MacDonald, a high school junior, said he’s learned valuable research and digital literacy skills from the librarian, things his peers in other schools may go without.

“The library is used a lot throughout the day,” MacDonald said. “Having a library has definitely been very beneficial to us.”