LITTLETON, Colo. (KDVR) — A group of principals who experienced school shootings released a Guide to Recovery on Monday. It’s a list of best practices for schools dealing with tragedy.

The guide was released by the National Association of Secondary School Principals/Principals Recovery Network at the Columbine Memorial in Littleton.

Former Columbine High School Principal Frank DeAngelis spoke on a panel about the guide along with other principals dealing with tragedy in their schools.

DeAngelis said he wishes he had a guide 23 years ago after the Columbine tragedy.

“It was a lot of trial and error. We didn’t know what to do,” DeAngelis said.

But, there were lessons learned by himself, and the other principals on the panel who unfortunately are also dealing with school shootings.

“The guide provides real accounts from real leaders in these situations and what they had to do,” said Michelle Kefford, the principal at Marjorie Stoneman Douglas High School in Parkland, Florida.

“We are right now going through a sentencing trial for the shooter and that is opening wounds,” Kefford said.

She added that needs change over time, and the group of principals is there to answer questions and help each other.

Now they want to help others, and they are hoping that leaders in education will read their guide.

It addresses issues like the reopening of school, counseling needs and remembrance ceremonies.