The tax-free weekend began in 2000 as part of Gov. Jim Hodges' education initiative to give citizens a break on the cost of school supplies. The idea may have had merit, but, largely because of price manipulations by retailers, the savings are largely illusory.

"I have some real problems with the sales tax holiday in the sense that it's ultimately a political gimmick that offers minimal impact on the economy and offers minimal savings to the taxpayer," Sanford said.

Supporters of the holiday point to figures indicating that shoppers collectively save millions by not paying sales taxes. For example, during the first year, South Carolina shoppers did not have to pay $3.6 million in sales tax they otherwise would have. In 2002, the figure was $3 million, and in both cases some of that represented genuine savings.

But research of tax-free holidays indicates that retailers usually offer less generous markdowns and cut down on promotional sales on the weekend that taxes are exempted. A 2002 study by the University of West Florida found that shoppers could have saved more on 95 selected items if they had bought them the weekend before the tax-free holiday.

According to the same study, shoppers also could have saved money the week after the holiday when many items that didn't sell during the tax-free weekend were marked down. Thus, while the promise of being able to buy items at 5 to 6 percent off the normal price might be a good way to entice customers to go shopping, it may be a false savings. After all, even a 10 percent markdown is better than what is saved by eliminating the sales tax.

One of the benefits of the tax-free holiday in the early years was that it lured customers from North Carolina to South Carolina stores. Last year, however, North Carolina decided to schedule its tax-free holidays on the same weekend as South Carolina's to cut down on the migration of shoppers across the state line.

The tax-free holiday may get shoppers into the stores, which is good news for retailers and probably a small boost for the overall economy. But the estimated $3.1 million shoppers are expected to "save" this weekend represents $3.1 million in lost revenue for the state. And during these lean times, that hurts.

Weighing the pros and cons, savvy shoppers might do well to wait until the weekend after the tax-free holiday to buy their back-to-school supplies.

Shoppers probably can save more by getting school supplies on another weekend.