Prosecutors said Rodriguez stabbed the victim on the campus of Sonora High School in La Habra on the morning of Sept. 8, 2009. Rodriguez was not a student at that school but the victim is identified as a member of a rival gang.
Investigators said the two began staring at each other, flashing gang hand signs and making aggressive comments.
A fight broke out during which Rodriguez stabbed the victim on the right side of the head and the left shoulder blade.
The victim was taken to a hospital. He has since recovered.