Cano, then 17, was charged in 2011 with threatening to discharge a destructive device, possession of bomb-making materials and several drug-possession crimes, and will be sentenced Dec. 5 after he pleaded no contest to the major charges, ABC News reported.
In the video, Cano explains how he intended to blow up Freedom High School, occasionally stopping his rant to smoke marijuana.
"My plan is to set a bomb here at Point A, here at Point B, Point C and Point D. Then I got to get to the side entrance of the school by 7:24. The bombs blow at 7:26," is some of the dialogue heard on the video.
A friend of Cano's tipped off the police, leading to the arrest. Investigators found a written manifesto and detailed illustrations of the plan, ABC News said.
"We were probably able to thwart a catastrophic event," Tampa police Chief Jane Castor said.