Guyana-born Rucawatee Autar was looking to improve her reading and writing skills when she began taking adult literacy classes at the New York Public Library.

But Autar decided that the library’s four hours a week of class were not enough, and she started searching for an alternative. In early July, she thought she had found it, in the form of the city education department’s Office of Adult and Continuing Education.

Yet after completing an intake exam at the office’s Mid-Manhattan Adult Learning Center, Autar says she was told to return to the library. Her scores were too low for her to enroll in the department’s courses.

“I don’t think it’s fair,” she said.

Ultimately, Autar was able to negotiate her way into a department class that was slightly above her level. But other students might end up at the library if principals at city adult education programs follow new guidance they received last month from the department.

That guidance, which urged principals to refer low-level students to free classes at the New York Public Library, has longtime adult educators worried that the department is shortchanging the office’s neediest adults. They say differences between department and library courses make the library classes less helpful for low-level students, who are either immigrants illiterate in their native languages or English speakers testing at a kindergarten or first-grade reading level.

The educators are also concerned that the department is steering low-level students away as part of a larger shift toward emphasizing test score gains over practical life skills.

The Department of Education has long sent students elsewhere when its own classes are full, according to a spokesman. He also explained that for some time the department has referred low-level students to the library or community organizations because they offer smaller classes.

But Betty Gottfried, who taught adult education in New York City for 42 years, said she had never before seen a recommendation from the department to send particular students away.

“We served everybody,” she said. “That was our mission.”

This past school year, the department’s adult education program served approximately 29,000 students — even though New York does not require districts to provide educational services for adults over 21. Starting in the fall, the department is actually adding 20 English as a second language classes, reaching students with a range of literacy skills.

“These adult ESL classes are important and widely popular, and we look forward to serving even more adults by expanding classes citywide during the 2014-15 school year,” said Marcus Liem, a department spokesman.

Regardless, some adult education employees see the library referrals as a diminishment of services by the department.

“There was always testing at intake, but the purpose of the testing was placement, not to determine whether you would be admitted or referred elsewhere,” adult education teacher Marcia Biederman said.

And Biederman and her colleagues are concerned that classes at the library are not a substitute for department courses.

For starters, the classes at the library provide just four instructional hours per week, compared to up to 15 hours a week for department-run classes. Unlike the department, the library does not have classes just for immigrants who are illiterate in their native languages, although it has recently trained its teachers to work with these students.

Library instructors also don’t need a master’s degree or state certification, which the department requires for its teachers.

“We look to hire staff with experience in the field and then provide them with training opportunities,” said Luke Swarthout, the director of adult education services at the library.

Swarthout said the Department of Education had not told him that it would start recommending students to library programs. He also said that even though the library has tripled its ESL seats in the last two years, it still attracts more students than it can serve — meaning that enrollment is not assured for students sent there by the department.

Teachers say they suspect the referrals are motivated by an office-wide shift that has taken place under Superintendent Rose-Marie Mills, who took over in 2012. According to them, Mills’s leadership has brought a new emphasis on showing test score gains, which are required for the state to draw federal adult education funds that it passes along to districts. This year, the city adult education office got $37 million from the state.

“At every single teachers’ meeting, we’re constantly reminded and told that the state is monitoring our data and we have to reach our target,” said Corinne O’Shaughnessy, who has taught basic education for the past five years.

“Before, the idea was to give people what they need,” O’Shaughnessy said. “They need to be able to go the doctor’s office, they need to be able to go to a school meeting for their child.”

O’Shaughnessy added that she used to take students to a subway station to teach them how to purchase MetroCards. “Now, if it doesn’t show gain on the test, you’re not supposed to do it,” she said.

And showing gains can be especially difficult for low-level students, according to teachers in the adult education office. Many of these students are attending school for the first time, and they often take more than a single year to show improvements or move up to the next course level.

Teachers also say the current assessments do not accurately reflect what the students learn. The test for immigrants in the lowest-level ESL course is oral, for example, while the class itself focuses strongly on reading and writing. And the exam for low-level English speakers asks about obscure topics, such as winterizing pipes, according to O’Shaughnessy.

Even as the scope of change at the Office of Adult and Continuing Education remains unclear, teachers say the signs are not promising, given that low-level students are being directed away. “It’s shameful,” Biederman said. “Really they are the neediest and most vulnerable of our students.”

Correction: This article previously stated that library instructors are hourly workers. In fact, while some of the library’s adult ESL instructors are hourly, most adult education instructors at the library are full-time NYPL employees.