COLUMBIA - Educators worry that lottery-backed scholarships tied to grades are deterring South Carolina's top students from taking advanced courses in their senior year of high school.

Melanie Barton, director of the Education Oversight Committee, said students are telling guidance counselors they don't want to jeopardize their chance of getting a scholarship by taking a tough course that could bring a low grade. It appears to particularly be a concern for students expecting to receive Palmetto Fellow scholarships, awarded to classes' top graduates.

The system may actually deter high-performing students from challenging themselves academically, instead of encouraging students to take Advanced Placement or dual enrollment classes that allow high school students to earn college credit, Barton said.

"Senior-year students are saying, 'Mom or Dad doesn't want me to take that AP chemistry class because they don't want to risk losing Palmetto Fellows.' But the student really needs it because the student wants to be pre-med. The issue becomes money versus learning," she said Tuesday.

The Education Oversight Committee does not yet have statewide numbers to back up what officials are hearing anecdotally. Gov. Nikki Haley's budget proposal for 2014-15 includes a clause that tasks the agency with investigating the potential problem and, depending on its findings, evaluating solutions. A report to Haley and legislative leaders would be due by Dec. 1.

"Gov. Haley believes that it is important to maintain high standards for academic scholarships, but those standards should not prevent students from taking on challenges and stretching themselves academically," said her spokesman, Doug Mayer. "Providing scholarships that potentially inhibit students from challenging themselves isn't the answer."

Barton said the reluctance seems to be a by-product of the economic downturn, which heightened parents' concerns about paying increasing tuition costs. Advanced Placement, International Baccalaureate and dual-enrollment courses are weighted more, for GPA purposes, but even a B can be a problem for students in schools where there's lots of competition at the top, she said.

Palmetto Fellows can receive up to $10,000 a year toward college tuition, depending on their major, if they earn at least a 3.5 grade-point average and graduate in the top 6 percent of their class.

Life Scholarships provide up to $7,500 a year for students with a minimum 3.0 GPA who rank in the top third of their class. Other students graduating with a 3.0 GPA qualify for Hope Scholarships that provide up to $2,500 for only the first year of college.