An Oregon teen has allegedly been planning in detail an attack on his high school and was hiding bomb makings in his room, including napalm.

17-year old Grant Acord will be charged with attempted aggravated murder after police–acting on a tip–found the napalm, pipe bombs, drain cleaner bombs, and Molotov cocktails in Acord’s bedroom, where he’d been hiding them under the floorboards. The teen reportedly had well-drawn plans to attack his school and wanted it to be on a bigger scale than the deadly Columbine shootings in 1999, when two teens shot up their school and killed 12 students and a teacher.

Acord’s “goal was to model the Columbine shootings with some adjustments that would make it a greater success,” District Attorney John Harlodson said.

West Albany High School has been searched as a precautionary measure, but officials will go through once more with bomb-sniffing dogs before students are allowed to return after the weekend.

Acord has been planning the attack for some time, and had diagrams and checklists in his bedroom which laid out his plans for the bombs as well as guns.

“This was a very methodical process,” said Haroldson. “He took time to even get to this point. “I can’t say enough about how lucky we are that there was an intervention. When I look at the evidence in the case, I shudder to think of what could have happened here.”