Gov. Nikki Haley signed a charter school bill Monday that advocates say will strengthen the state’s 47 public charter schools.

The bill enables higher education institutions to authorize charter schools, permits single-gender charter schools to operate and allows charter school students to participate in extracurricular activities at their neighborhood schools.

“The bill focuses on expanding high impact public school options for students across South Carolina,” said Mary Carmichael, executive director of the Public Charter School Alliance of South Carolina, in a statement.

South Carolina has outpaced national growth in the number of charter school students served during the past 5 years. Nearly 18,000 students statewide attend charter schools.

Eight new schools will open this year, 13 have been submitted for 2013-14, and more than 30 planning groups are working on applications.

Charter schools are public schools, but they aren’t governed by the county school board. They instead have separate boards to make decisions about the way they spend money and the curriculum they offer.