Shoppers can buy certain types of clothing and shoes free of state and local sales tax, but you need to remember that the sales tax holiday only applies to clothing and shoes priced less than $100. Accessories like jewelry, bags, watches and some types of athletic footwear do not qualify.

At Walmart, not only can you make tax-free purchases, but the stores also are offering deals on some school supplies that do not qualify for the tax free discount.

"We've rolled back the prices on 10 percent more school items than we did last year,” Walmart’s Erica Jones said. “We have hundreds of items that are less than $1 -- hundreds of items less than $2, less than $3 -- really low price points on items that are really popular.”

All retailers are required to participate in the tax free holiday weekend. It ends Sunday at midnight.

Since 2007, Oklahoma has held a tax free weekend to compete with ones offered in surrounding states.