The measure awaits the governor's signature after passing both the Tennessee Senate and House, WHBQ-TV, Memphis, reported.
"Just grownups making more rules, gonna break 'em anyway," said former high school student Ian Moss.
"Everybody should dress how they wanna dress, it's a free country," Trina Sanders told WHBQ.
If approved by the governor, the law would take effect July 1. It permits school districts to decide for themselves what punishment to give students who break the new dress code.