Dawson is peppering the class of 11 girls and four boys with questions, trying to keep everyone focused as she helps correct mistakes.
When a student gets one of the dense equations right, Dawson and the class salute with finger-snapping in place of applause
"I want some A's on Tuesday," the teacher says, warning of an upcoming test.
In a state where Republican leaders are trying to put their stamp on long-running efforts to improve education, Clarksdale is emblematic of both the challenges the state faces and innovative ideas for boosting schools.
Leaders of the city in the impoverished Delta region—known as the crossroads of the blues where Robert Johnson once lived—hope improved education will help stanch a hemorrhaging population that now stands at 18,000.
"Without a strong public school system, you have no growth in the community," said Lois Erwin, a former principal at a private school who's now coordinating a community development effort sponsored by a local bank. "You've got to have a strong public school system or you don't have economic development. That's just it."
Republicans' statewide solutions include making it easier to create charter schools and holding back third-graders who can't read.
"All those categories that we see that have an effect not only on quality of life, but on our society and workforce, go back to beginning with a failure in the educational system," said Republican Gov. Phil Bryant, who names education as key to improving Mississippi's weak economy. "There's nothing better that I could do than change what I think has been a fairly ineffective educational system."
The GOP-sponsored measures could mean more big changes for Clarksdale's nine public schools, which would be fine with local attorney and former Democratic gubernatorial candidate Bill Luckett.
"We need a cultural shift," said Luckett, who's now running for mayor of Clarksdale. "We need a big war; that's how I look at it."
Though Mississippi lags in education, it has made progress.
A Harvard University study found that Mississippi students posted greater gains on the National Assessment of Educational Progress than the average among the 41 states it measured. The state ranked 13th out of that group overall for improvement between 1992 and 2011.
In 1980, only 54.8 percent of Mississippi residents 25 and older had a high school diploma according to Census data, compared to 80.4 in 2010. Mississippi improved by 25.6 percentage points while the nation improved 13.9 points to 85.3 percent. The improvement was even steeper in Coahoma County, which includes Clarksdale. The share of adults with a high school diploma rose from 43.8 percent in 1980 to 75 percent in 2010.
But the Harvard study finds that while Mississippi has been able to boost many of its students up to basic achievement levels, most are not yet truly proficient. And while Mississippi has many more high school graduates than 30 years ago, American-born Mississippi adults are still the least likely of those in any state to have a high school diploma.
Improvements are toughest in areas such as Clarksdale, where per capita income is about 78 percent of the national average and the unemployment rate was 13 percent in March. Half of all county children live in poverty, and 90 percent of Clarksdale's 3,200 students qualify for free or reduced-price lunches. Most white children attend private schools, while 97 percent of students in the public system are black. Of children born in Coahoma County, 18.8 percent have a low birth weight. That critical predictor of future problems is more than twice the national rate of 8.1 percent.
Beth Fulmer, a rookie teacher at Oakhurst Middle School, says poverty is a destabilizing force that her students struggle with. "I think a lot of a child's success comes from their home lives," she said.
Superintendent Dennis Dupree's profile is rising as he tries to lift achievement levels in Clarksdale. Since Dupree was appointed in 2007, the district has won grants to improve its high school and one of its two middle schools. Clarksdale was one of the first three districts statewide to adopt a more rigorous high school curriculum. After piloting it with 40 students, Dupree plans to roll it out for all 9th graders next fall. He's also volunteered Clarksdale as one of four districts to experiment with paying teachers based on performance, a pilot program meant to help Mississippi develop a merit pay system for all teachers. And Dupree is one of a group of educators who designed a new scoring system to grade schools statewide.
Dupree says his ultimate goal is to vault Clarksdale into the top rank of Mississippi districts.
"We've been seeing improvement, Dupree said. "We know we've been seeing it."
Many say Dupree is at least chipping away at the schools' failings.
"I feel like they are doing a fairly good job," said Lamar Hicks, a Clarksdale High graduate and former assistant teacher who has a son in first grade. "They are doing exactly what they can do."
There's still a long way to go. The overall district and Clarksdale High School were exempted from Mississippi's A-to-F school grading system last year because of the high school curriculum pilot. Results from elementary and middle schools were mixed. Two of six elementary school got B grades. But two elementary schools and both middle schools were graded F.
One big change coming in Mississippi is a requirement to hold back children in grades K-3 who aren't reading at grade level. That's modeled on laws adopted in Florida and 13 other states.
Clarksdale's elementary schools are trying to improve student literacy. Valarie Davis, principal at Myrtle Hall IV Elementary, said the biggest reading challenge is lack of preparation at home, reflecting poverty and low parental education levels.
"The children don't have the background," Davis said. "Some of them have never been read to or read books at home."
Preschool preparation for kindergarten could ease that problem. Mississippi has been the only state in the South and one of only 11 nationwide with no state-funded preschool program. But lawmakers approved a plan for school districts, Head Start centers and private child care operators to jointly provide voluntary preschool for 4-year-olds. Clarksdale is already using federal money to run three 20-student preschool classes, putting it among the one-third of Mississippi districts doing so even without state aid.
Clarksdale could also be an early target for a charter school under a new law easing creation of the alternative public schools. The Knowledge is Power Program, a national group, operates a charter school in nearby Helena-West Helena, Ark. The group has expressed interest in Clarksdale and many Mississippi leaders have said the school is a model. Some Clarksdale residents, including Luckett and his mayoral rival, Democratic state Rep. Chuck Espy, also support charter schools.
Dupree says the public school system is striving to be so attractive that parents will choose public schools even if a charter school opens.
"When there's choice, we want to be the choice," he said.
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