Students at Woodbridge Senior High School wore red Monday -- the favorite color of a fellow classmate who died over the weekend.
A passerby found Kenny Joseph Diaz, 18, bleeding from an apparent stab wound to the stomach around 3:15 p.m. Saturday.
Diaz, still breathing, was laying near a footpath at the Marumsco Acre Lake Neighborhood Park in Woodbridge.
That person called 911, and Diaz, of Woodbridge, was taken to a local hospital, where he died.
"He was really friendly, like I would never see him upset.... He wasn't the person getting in fights," said childhood friend Joaquim Santos. "He was like the average good kid. I wish he was still with me. I wish I could see his face again, talk to him, tell him I miss him."
Diaz was a senior at Woodbridge and played for the school's football team. Grief counselors were at the school Monday to help students cope with his death.
"I just think it's really tragic to see another young person just die [in] high school," said classmate Samanthia-Rae Poole. "They don't get to live their whole life."
Diaz's friend Andrew Collins said he couldn't believe the news at first. "It was just last week, we were chilling, and now, he's gone," Collins said.
An investigation into Diaz's death is ongoing.
Prince William County Police haven't released a lot of information, but they say the stabbing did not appear to be random.
A funeral mass for Diaz is scheduled Friday afternoon at Our Lady of Angels Catholic Church in Woodbridge.