The student, whose name was not disclosed, was studying at Ygnacio Valley High School in Concord in California. He has been suspended, a school spokesperson was quoted as saying by Xinhua news agency.
According to police, the student targeted teachers through a phishing scam and hacked into the Mount Diablo Unified School District computer system, a public school district in Concord that operates several schools, in an attempt to change his grades and those of other students.
"We wrote numerous search warrants to get the IP addresses of the possible phishing site email... We did good old-fashioned police detective work and we narrowed it down to an address," Carl Cruz, the Concord Police Financial Crimes Supervisor, was quoted as saying.
The student successfully managed to change the grades.
The high school student had created a fake website and e-mailed teachers in a phishing attempt to get their log-in details.
One teacher actually logged into the fake website, making it possible for the student to access the grade system, police said.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)