Chesterfield, S.C. ? An 18-year-old straight-A student accused of planning to bomb his high school was charged Tuesday with attempting to use a weapon of mass destruction, which carries a possible life sentence.

The charge is one of three federal counts Ryan Schallenberger faces in what authorities say was a scheme to detonate explosives in a suicide attack on his high school in the small town of Chesterfield.

Schallenberger also faces charges in state court, where he appeared for a hearing Tuesday. Cuffed and shackled, the teenager smiled and gave a quick wave to courtroom spectators, including his parents and some classmates.

After the hearing, Chesterfield County prosecutor Jay Hodge said investigators found a timeline for an attack in Schallenberger’s journal. The entry, made last month, included how he would lock his school’s doors and where he would place more than five explosives in the building, Hodge said.

Hodge said the 50-page journal also contained some attempts at self-analysis and that the teenager knew that what he was planning was wrong.

“The kid needs help, but this is a violent offense,” Hodge said. “You can’t put an entire community in fear and just walk away. In this situation, society requires jail time. There’s no way to excuse or forgive what he did.”

Schallenberger was arrested on state charges Saturday. Authorities say his parents called police because he had ordered 10 pounds of ammonium nitrate, which they retrieved after getting a delivery notice from the postal service. Ammonium nitrate is a fertilizer that was a component in the deadly 1995 Oklahoma City bombing.

Authorities have said Schallenberger could have assembled deadly bombs within minutes with the materials they found. Police said they also discovered bombing plans including a hand-drawn map of the school, praise for the Columbine killers in his journal and an audiotape that authorities say was to have been played after Schallenberger died.

State prosecutors on Tuesday formally requested to change the state charge from making a bomb threat to possession of bomb-making material, which carries a sentence of two to 15 years in prison.

Defense attorney William Spencer, who was appointed for the state case, said the teen doesn’t want to post bond or have a mental evaluation, which prosecutors had talked about seeking. Spencer said that after meeting with Schallenberger a day earlier, he believed his client was competent to defend himself and understand the charge against him.

The federal charges will be handled before the state counts and come into play mostly because Schallenberger ordered materials that can be used for bombs through the mail, said Kevin McDonald, the acting U.S. attorney for South Carolina.

McDonald said Schallenberger waived his right to a preliminary hearing Tuesday. Attorney Michael Meetze, appointed as the teenager’s defense lawyer for the federal charges, did not return a call from The Associated Press.

One classmate disputed characterizations of the teen as a loner. Hanna Huntley recounted how the teen made students laugh by singing songs from the cartoon “SpongeBob Square-Pants.”

“He had plenty of friends,” the 18-year-old said. “He was a likable person. He was the type of person that, if you weren’t happy that day, he’d make you smile. That’s why it was such a shock. He obviously kept all this bottled up.”