When Elias Velazque moved with his family to Roseland from Mexico at the age of 4, his construction worker father and stay-at-home mother had trouble providing school supplies and books for the young student.

Now a freshman at Roseland University Prep in Santa Rosa, Velazque and his classmates spent Wednesday morning packing backpacks full of pencils, crayons, scissors and bilingual “Curious George” and “Big Dog, Little Dog” books. The care packages will go to 3- and 4-year-olds in his Roseland neighborhood and around Sonoma County whose parents also struggle to afford the tools their children need to succeed in early education.

“When I was small, we didn’t have much,” said Velazque, 15. “My parents tried everything to get me the right materials. Helping here, it makes me realize there are kids just like myself. I know I’m helping some kid who can’t afford some things have a better opportunity in life.”

More than 100 Roseland Prep students, fueled by doughnuts and music and organized in a five-classroom assembly line, on Wednesday put together 1,200 of the school readiness kits that are designed to help parents encourage reading at home. Sponsored by the United Way with support from Wine Country Weekend and the Community Foundation of Sonoma County, the program has made a positive impact on families and children since it started last year.

“It gets books in the house,” said Andrew Leonard, education program officer for the United Way of the Wine Country. “A lot of the families don’t have any books in the house.”

Through follow-up surveys, the United Way found that there was a 14 percent increase in parents who report reading to their children after receiving the kits. More than 90 percent of parents surveyed said they used the nonreading activities included in the backpacks.

Many of the school readiness kits will go to low-income families in Roseland. The high schoolers lending a hand get the satisfaction of helping out their neighborhood, said Jenn Del Rosario, community relations coordinator for Roseland Prep.

“They get a sense of empowering their community,” she said. “Our philosophy is we want kids to go to college and then come back to the community and be role models.”

Amid the bustle of sorting, stacking and packing on Wednesday, Jerely Figueroa, a 14-year-old freshman, filed reading materials in English and Spanish into a resource binder included with the kits. She said that she knows several Roseland families who could benefit from the learning activities and other supplies.

“These are for kids who can’t afford school supplies,” she said. “Some parents work two jobs and still can’t afford to buy stuff for their kids.”

Into each binder, Nancy Trejo, 14, inserted an application for a Sonoma County Library card in the hopes that parents sign up and take their kids to the library.

“They can get the books they need,” she said. “It makes me feel great helping out.”