A new survey of 17-year-olds found that when asked which year Columbus sailed the ocean blue, 26 percent did not say 1492, CBS News correspondent Ben Tracy reports.
And a whopping 57 percent did not know the Civil War happened in the last half of the 19th Century.
At one high school in Oakland, Calif., the students were pretty sharp.
Tracy asked one, "Which American poet wrote Leaves of Grass?"
"I want to say Walt Whitman," the student said. And was correct.
But other historical names, like anti-Communist crusader Sen. Joseph McCarthy, have been, well, blacklisted.
"What was the big controversy that surrounded him?" Tracy asked.
"Is he the Senator that did the bathroom stint?" one student said.
The author of a new book, "The Dumbest Generation," says teenagers are too distracted by computers and social networking.
"They don't care! That doesn't' touch them" said Mark Bauerlein from Emory University. "There's no reason for them to care."
He added: "This is what is crowding out the materials of history, civics and so on."
But a lot of educators say all this talk about the dumbest generation is really quite stupid. They say high school is more demanding than it's ever been, and students don't need to know a litany of dates because they can just Google them.
"You helped teach this generation - do you take any offense to any of this?" Tracy asked Bishop O'Dowd High School's Steve Phelps.
"I know that this generation is the smartest we've had," he said.
Phelps teaches at the Oakland high school. He says students are expected to analyze events and concepts rather than recite dates.
"People think that not knowing the old information means you're not educated," he said. "But they don't look at what this generation knows today."
Closing that gap between teens and their parents may be the real test.