It is a thought shared by many parents that awful day, reports CBS News Correspondent Cynthia Bowers.
Rachel and Don Lee learned their son Shawn escaped from Columbine just as the shooting began. But they were not concerned about daughters Becky, a freshman and Beth, a sophomore.
"I knew where my daughters were; my daughters were home," says Rachel. Home, being home-schooled.
"I could have had two more kids in that building as well," says Don. "So it really reinforced to me that we made the right decision to homeschool our daughters."
Becky and Beth still aren't so sure.
"I miss having a class full of kids," says Becky. "I miss the diversity and stuff."
But their parents contend Columbine's school environment was getting bad, even before the rampage. They pulled the girls out after a friend of Beth was attacked by five male students in Columbine's parking lot.
Don Lee, a Colorado state representative, was incensed nothing was done. "They pulled her top off and took pictures of her," says Lee.
As many as a million-and-a-half American children are home-schooled. And the numbers are rising, up 15 percent over the last five years. In Colorado the Department of Education says there was about a 60 percent increase in requests for information about home-schooling after Columbine; but very few people are following through.
That might be because of the time commitment and the perception that home-schooled children become isolated.
But Rebecca Rupp, the author of Getting Started On Home Learning, How And Why To Teach Your Kids At Home, says home-schooled children are actually very well-socialized.
She told CBS News Correspondent Russ Mitchell "there are community things they participate in. Most have support groups, other friends who are home-schooling. Studies have shown they are very skillful socially."
Rupp also denies that home-schooling is expensive, even though parents have to purchase all the books and supplies for their children.
"Studies have shown that the average home-schooler spends around $500 a year per kid," says Rupp. "Some home-schooling expenses are hard to separate from what you'd spend just raising your kids anyway."
And, she says, most parents are capable of teaching kids the things they learn in school.
"You grow into it. It's a learning process," says Rupp. "If you can read, you can research, you can find resources for your children. There are any number of resources out there for home-schoolers. The other thing about home-schooling is that you don't leap into calculus. Most people start when their children are young. You learn together."
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