New data shows that Chicago Public Library’s free after-school homework program, the largest in the country, assists students who have “the greatest need for additional educational support,” CPL announced in a news release Wednesday.

Chicago Public Schools and Chapin Hall, the University of Chicago’s policy and research center, found that students who use the Teacher in the Library program generally have lower standardized test scores than their peers before beginning the program, according to the news release. Further, 90.5 percent of participants receive free/reduced-price lunch, compared to 84.2 percent of their peers.

CPL Commissioner Brian Bannon said the collaboration with Chapin Hall has allowed CPL to maintain its “integrity as a public institution” while using data to support educational outcomes and the city’s larger goals.”

“We finally have concrete data that shows we’re heading in the right direction,” Bannon said. “What we’re doing in Chicago is unique, and it’s allowing us to help other cities do the same thing.”

Teacher in the Library offered nearly 100,000 after-school sessions during the 2016-17 school year, marking a 68 percent increase within four years, said CPL spokesperson Alexandria Trimble. It launched in 2000.

CPL Commissioner Brian Bannon (right) gathered with library staff and spokespersons at the Chinatown branch library on Wednesday. | Chicago Public Library photo

Data also showed that Teacher in the Library participants are more likely to be learning English as a second language. Eslavia Garza, who was a CPS teacher for 27 years, mostly teaches Spanish-speaking students. She said their parents love the program.

“The only concern that they have is that they wish they could have more of it,” she said. “If (students) don’t get help from the library, they don’t get any help at all. … So that’s why parents want more of it — they see the difference.”

Mayor Rahm Emanuel said in the news release that the program furthers libraries’ role in the city by assisting students “most in need of our support.”

“I want to thank Chapin Hall for evaluating the program and validating what we already know – every investment made in a child is a down payment on their future and the future of the City of Chicago,” he said.

Next week, CPL will launch its annual Rahm’s Readers Summer Learning Challenge, which has evolved since 1997 from a summer reading program into an expansive effort to combat loss of learning during summer. It reached 105,000 students last year, Trimble said, and it offers active, hands-on learning opportunities for infants to 13-year-olds.

Earlier Chapin Hall findings showed that participants showed 15 percent greater reading gains and 20 percent greater math gains when compared to non-participant peers, according to a 2016 CPL news release.

This year, the summer program will tackle topics of earth systems and environmental literacy in partnership with the Art Institute of Chicago and the Lincoln Park Zoo, among other institutions.