Photographer Andres Gonzalez wanted to create a book about how communities process trauma after mass shootings at schools. He has spent the past five years documenting the aftermath of mass shootings in American schools.

Gonzalez spoke with NPR's Audie Cornish about what he found as he visited Virginia Tech, Columbine, Newtown and Parkland to photograph what Cornish called tangible pieces of grief.
"Crosses, Jewish stars, angels - a lot of angels," Gonzalez recounted. "I found a lot of origami cranes."
But his investigation started with a visit to a campus in DeKalb, Ill., where five students had been killed in an attack on Feb. 14, 2008.
"The very first place I visited was Northern Illinois University," Gonzalez said. He met with a librarian at NIU who told him the school had saved the things left at makeshift memorials after the attack.
"She showed me a few items, but what I wasn't really expecting was to see the massive amount of material that they had collected. It just went on and on and on," he recalled. "And I still wasn't sure what question I was asking. I didn't know that the memorabilia would be such a big part of the project. But that was the introduction to the work."
His forthcoming book is called American Origami.
Like several of the other locales, NIU has created a digital archive of mementos sent to the school and to families of victims of the tragedy. It includes items sent from Virginia Tech, where 33 people were killed on campus the year before the NIU shooting as well as items left at makeshift memorials on campus.