Prosecutors say Abraham Ali was trying to be subtle when he hacked into his school's computer system and changed two failing grades to Ds.
What he apparently didn't count on was causing the entire system to crash, prompting an investigation that resulted in his arrest on felony charges.
On Thursday, the former student at Glenbard South High School in Glen Ellyn pleaded guilty to a reduced charge of misdemeanor attempted computer tampering.
In exchange, he received two years of conditional discharge and was sentenced by Judge Blanche Hill Fawell to 60 days of jail work release and 20 days in the DuPage County Sheriff's Work Alternative Program.
Ali, 21, formerly of Glen Ellyn, was nearing graduation when he used a "password-sniffing" program to break into Glenbard High School District 87's internal computer system in early 2009, according to prosecutors.
The access allowed Ali to change two grades -- in English and math. In one class, he graded himself on quizzes and assignments from days when he wasn't at school, Assistant State's Attorney Diane Michalak said.
Ali came under investigation and was indicted after the tampering caused the school computer system to crash. He later was expelled, authorities said.
"He admitted to school personnel that he changed grades from Fs to Ds in two classes, and that he was trying to be subtle," Michalak said. "He also bragged to two classmates on separate occasions about his ability to fix grades."
Michalak said the system shutdown lasted about 90 minutes and prevented the school from accessing voice mails, its internal database and web-based classroom materials. She said Ali already has paid $11,600 in restitution to cover repair costs.
Ali, who now lives in Chicago and attends College of DuPage, could have faced up to five years in prison if convicted of felony computer tampering and computer fraud. His attorney could not immediately be reached for comment.