They spent all summer reading. On Wednesday, families who participated in the county library’s summer reading program enjoyed a carnival to celebrate their prolific appetite for books. The summer program at the Hancock County Public Library in Greenfield and New Palestine ends next week. A total of 3,837 children, teens and adults participated in the programs, reading nearly 50,000 books. Participation increased at all age levels, with 544 more people than last year. The biggest age group to see an increase was adults: 16 percent more grown-ups participated in the program this summer compared to last year, library officials said.