(CBS News) MOORE, Okla. - The mayor of Oklahoma City said Wednesday as many as 13,000 homes were damaged or destroyed in Monday's tornado, and 33,000 people have been affected. The mayor says the damage could total $2 billion.
The state medical examiner said there were 24 deaths. Two were infants: four months old and seven months old.
Most of the children who died were in school. And parents are asking why those schools don't have shelters.
Helen Grant rode out the tornado in her neighbor's underground shelter in Moore. She thought her two daughters were also in a shelter at their nearby Central Elementary School. Instead, they huddled in a bathroom.
"I'm really upset," she said. "I know there were shelters in some schools and the fact that there aren't shelters in other schools just shows disparity."
Seven children were killed Monday when the tornado destroyed Plaza Towers Elementary in Moore, which did not have a shelter.
There is no state law in Oklahoma requiring schools to have safe rooms or tornado shelters in schools, despite the increased risk of tornadoes there.
Albert Ashwood, Oklahoma's director of emergency management, says they have built safe rooms in about 100 schools, but its costly.
"Most of these projects have been between $600,000 to $1 million and usually applied to brand new construction of new schools," he said.
Grant doesn't think money should be an excuse.
"I don't think you can put a price on human life," she said. "And even if the storm doesn't hit your town in the next 20 years, you're making an investment in the children of the future."
Right now, many children in Oklahoma schools are instructed to take cover in bathrooms or hallways.
But according to the state's own insurance commissioner, John Doak, hallways can't protect against the strongest storms.
"It's not a safe enough place for kids, in an EF5 tornado, with 200-mile-plus winds," he said. "Anything above ground, as we can see, is going to be taken off."
In Moore, Mayor Glenn Lewis says he plans to push for new houses to have shelters or safe rooms. Right now, he said there is no requirement.
"It's been a free market society," he said.
After 1999, he said, local building codes were tightened to require stronger metal clamps to secure roofs on houses. The mayor said 2,000 shelters were built in private homes, but he didn't believe it was necessary to require them until now.
"Who thought we'd would have an EF5 tornado happen in same place twice?" he said. "We're just hoping it doesn't happen again."
Alabama is the only state that requires "safe spaces" to be built in new schools, according to the National Storm Shelter Association. That law was passed after a tornado in 2007 that killed eight children.