OAKLAND -- As news spread late Sunday about the killing of Osama bin Laden, some social studies teachers in the East Bay scrapped their lesson plans to make way for a discussion about a pivotal moment in American history.

"Is this vengeance, or was this a military necessity?" Michael Sagehorn, a former marine officer, asked his 12th-grade government students at the Oakland Military Institute, a charter school in North Oakland.

Sagehorn's students were only in third grade during the Sept. 11, 2001, terror attacks orchestrated by bin Laden and his followers. On Monday, their class and many others dissected the meaning of the al-Qaida leader's death and debated whether it should be celebrated as a victory for the United States.

Ronisha Spivey, 19, of Berkeley, speculated that the successful raid on a compound in Pakistan will only cause the global conflict to escalate.

"We killed one of (al-Qaida's) people," she said. "They're going to counterattack on us."

At Moreau Catholic High School in Hayward, 10th-graders in Frank Knight's world history class compared news articles from Fox News and MSNBC and tried to reconcile factual differences in the reporting. Knight said the teenagers were captivated by the story -- "the whole story" -- and wanted to learn more about it.

Such major global developments are invaluable for a history teacher, he said. "It's real life. It's not something that they see so far removed from their lives."

Kandi Lancaster, who teaches social studies at Walnut Creek Intermediate School, said many of her students didn't think it was right for Americans to be celebrating bin Laden's death in the streets. A lot of students, she said, feared retaliation.

Lancaster replayed President Barack Obama's speech for her classes. She said her students -- who were only 2 years old in September 2001 -- approved of Obama's tone and appreciated the way he explained the incident factually.

"They truly do understand the difference between the Taliban, al-Qaida and the majority of Muslims. They really get the difference between religious fanatics and everyday believers."

Whether students realize it or not, bin Laden's death will be remembered in history books, just like the death of President John F. Kennedy, Lancaster said.

"I was in the seventh grade when Kennedy was shot," she said. "It may not mean anything to them now, but someday when their kids are studying it, they'll say, 'Oh, yeah, I was in Mrs. Lancaster's class.' It's one of the markers of our life."

Erin Bodwell, who teaches eighth-grade social studies at the Oakland Military Institute, said bin Laden's death serves as a reminder of how long the nation has been at war. Her students, she said, are too young to remember peacetime.

Most of the military school's graduates are bound for four-year colleges. However, two or three from each graduating class typically go into the service, Sagehorn said.

Miguel Avila, 18, is one of them. He shares some of his classmates' concerns about the future; those fears are compounded by a recent, six-year commitment he made to the Marine Corps Reserves.

"I plan on staying home and going to college, but my life could be put on hold if there's a conflict," he said. "I can't turn back now."

Read Katy Murphy's Oakland schools blog at IBAbuzz.com/education. Follow her at Twitter.com/KatyMurphy.