A Mecklenburg County grand jury heard Jatwan Cuffie's case on Monday and indicted him on second-degree murder charges.
Authorities last month charged Cuffie, 16, with first-degree murder after he was accused of shooting and killing his classmate, 16-year-old Bobby McKeithen, in the hallway of Butler High School.
Officials said the shooting stemmed from an off-campus fight.
By law, prosecutors cannot discuss business with the grand jury, so it is unclear why the charge was reduced.
The superintendent of Charlotte-Mecklenburg Schools last week announced new security measures for schools, according to WSOC-TV.
>> On WSOCTV.com: CMS steps up security in the wake of a series of issues at local schools
After winter break, the district will begin using metal-detecting wands randomly on students and implement random bag searches, increased camera monitors and teacher panic cards.
The Cox Media Group National Content Desk contributed to this report.