This anniversary is especially meaningful for graduating seniors. They were freshmen on the day of the massacre.
The gunman, Steven Kazmierczak, shot and killed Catalina Garcia, Julianna Gehant, Ryanne Mace, Daniel Parmenter and Gayle Dubowski. Twenty one people were wounded. Kazmierczak took his own life.
"I saw the people who were hurt and bleeding, running and trying to help them. We didn't know what was going on. When someone came and told us, it was almost just trying to put everything together. It was like you understood what was happening, but you didn't really understand the whole situation," recalled Jack Thorne, NIU senior.
Five wreaths were placed at a memorial for the victims Monday afternoon.
"Catalina, Gayle, Julianna, Ryannne and Dan: our message to you is we have not forgotten," said John Peters, NIU president.
Although President Peters promised not to forget, many already have.
"People are talking about their dates and plans for tonight. And so we're actually tonight going to have a private ceremony for Dan outside our fraternity house, we have a little plaque up, we have a little tradition that we do there," said Scott Wolff-Klammer, NIU senior.
Those who won't forget are the families. Joe Dubowski lost his daughter Gayle that day. He has since written a book entitled "Cartwheels in the Rain" and enrolled in a graduate program at NIU that will some day enable him to help others going through loss.
"It's our tendency to run from memories and run from pain and things like that. And so it really helped me as far as keeping it fresh in my mind and to completely process what we had faced," said Dubowski. "I didn't want to run away from it."
NIU has launched a website that brings together the visuals and written archives of that day. There is a spot for people to submit their own stories and remembrances: www.february14.niu.edu
Cole Hall, the site of the shootings, has remained closed since the murder spree. Three years ago on Feb. 14, the gunman entered a geology lecture and opened fire at the DeKalb school.
NIU officials have started to renovate the building. The lecture hall where the shooting took place will be replaced with an anthropology museum and computer lab.
Kelly Wesener, an assistant vice president at the university, says even though time passes, the campus continues to heal.