Louisiana ranks sixth in the nation in the strength of its charter school laws, a group that calls itself the leading advocacy organization for the schools said.

The findings are included in a report set for release on Tuesday by the National Alliance for Public Charter Schools.

“Louisiana overhauled its law in several areas, resulting in a large jump in the ranks from 13th to 6th,” Todd Ziebarth, vice president for state advocacy and support with the group, said in a prepared statement.

Charter schools, which are legal in 43 states, are public schools run by nongovernmental boards.

They are supposed to offer innovative alternatives to traditional public schools.

The state has 104 such schools with about 45,000 students in 15 parishes, including East Baton Rouge. New Orleans has one of the largest presences of charter schools in the nation.

Applications for new charters shot up by five times last year over 2011, mostly because of a new state law aimed at helping Louisiana’s lowest-performing districts.

The law was one of a series of steps pushed by Gov. Bobby Jindal, and backed by the Legislature last year, designed to increase the number of charter schools.

Among other things, new laws require local boards to use the same timelines, standards and common applications as Louisiana’s top school board; eliminated a rule that most charter school teachers have to be certified and expands the authority to approve charters to community groups, nonprofits and universities that win state approval.

Backers contend that charter schools are an alternative to failing public classrooms.

Last year 36 percent of the state’s roughly 1,300 public schools were rated “D” and “F” for school performance.

Opponents contend the charter schools have failed to provide promised breakthroughs in improved student achievement.

They also say the schools have siphoned money from traditional public schools amid four consecutive years of freezes in state aid.

Minnesota is rated as the state with the strongest charter school laws in the nation.

Mississippi is listed as last, or 43rd nationally.

The rankings are based on 20 topics that the group considers vital to establishing laws that promote quality charter schools, including accountability, funding and whether the state has a cap on growth.

The group has issued its rankings for four years.

In 2010, Louisiana was listed as having the ninth-best charter school law in the nation. But 19 months later state education leaders said key changes were needed to improve oversight.

Those changes followed the state’s revocation of the charter for Abramson Science and Technology School in New Orleans amid allegations of sexual abuse and other problems.