NASHVILLE (AP) — Tennessee's high school graduation rate is up and assessment tests taken by elementary and middle school students improved last year, according to data released Thursday by the Education Department.

The figures show the graduation rate for the class of 2012 increased from 85.5 percent to 87.2 percent, and that elementary and middle school students grew in 23 out of 24 Tennessee Comprehensive Assessment Program measures.

Education Commissioner Kevin Huffman said he's pleased with the improvements, but there's still a lot of work to be done.

"We feel good about our progress last year, but we also feel there is a long way to go before we would feel close to satisfied by the way things are going," Huffman said.

For instance, he said many school districts did not successfully narrow achievement gaps, and there were declines among particular student subgroups.

Huffman said one gap he plans to focus on closing th is year is the one between students with disabilities and the students who are in special education, and their peers.

He said "professional development and better training" will help.

Huffman said the data, which is on the department's website, can be viewed by grade level, subject and subgroup for each of the 136 districts and 1,784 schools in the state.

"We think it's important for parents and students, as well as school and district leaders, to know how well their schools are doing each year," he said.

Earlier this year, U.S. Education Secretary Arne Duncan congratulated Tennessee on its continued statewide improvement on the Tennessee Comprehensive Assessment Program.

Tennessee became one of the first states to win Race to the Top funding in 2009 and went on to receive a waiver this year from certain parts of the No Child Left Behind education law.

"Through Race to the Top, Tennessee took on extraordinarily difficult work in a relativel y short period of time," Duncan said. "Early signs of widespread academic progress are not only encouraging but inspiring, and will help lay the ground work for further success as Tennessee continues its commitment to leading the nation in education reform."

Under its waiver, Tennessee proposed raising overall achievement by at least 3 percent each year and to cut achievement gaps in half over an 8-year period.

To track progress, the state was required to divide schools into categories with targeted interventions or rewards for each group.

For instance, some schools will be recognized for their high performance and rapid growth. Others will be targeted for low proficiency and large achievement gaps between subgroups of students defined by race, economic status, disability and English skills.

"Tennessee is focused on continuous growth, and our report card shows us where we are making gains and where we need more work," Huffman said.