Closing schools won't necessarily stop the spread of swine flu.
What about the younger sister in a private day care center? And how to keep teens who are sent home from getting together at the mall or at each other's houses?
So far, only about 100 of the nation's 132,000 schools have closed. But they include schools on both coasts and in the nation's heartland, and more are likely to shut their doors in coming days. Texas officials just suspended all high school sports — smack in the middle of baseball season.
In a worldwide epidemic — which the swine flu outbreak is not — government planning documents say schools could be closed for up to 12 weeks.
Local officials make the decisions on schools, after weighing conditions in their cities, towns and counties. But President Barack Obama says parents everywhere should start preparing for the possibility that their kids may be sent home.
That would raise a whole new set of questions.
"There is a large ripple effect," acknowledged Kathleen Sebelius, Obama's newly approved health secretary. "What happens to the parents? Where do those children go? Do you close the day care center if a younger sibling is there?"
So far, closings have affected fewer than 60,000 students out of a total of 56 million enrolled nationwide in K-12 education in public and private schools. Most of the closings are individual schools, not entire systems. Most are expected to be short-term, a week or so. Some of the children who got sick are already recovering.
If the outbreak turns into a killer flu, classes could still continue even if schools are shut.
If they've planned for it, teachers could give their lessons by Internet, television, radio, telephone, mail or through their community newspapers.
In Mexico, where the illnesses have been more severe, the government closed schools nationwide. In the U.S., authorities will deal with the problem from the ground up, not from the top down.
"It is the state and local role to plan what's going to happen, as far as day to day or hour to hour," said Brenda Greene, director of school health programs for the National School Boards Association.
If a flu case is confirmed at a school, local officials may just close down that school alone. Clusters of cases at different schools could prompt the closing of an entire system. Closings in many communities may lead to a statewide shutdown.
Closing schools is not to be taken lightly.
"It's not just about the schools," explained Kim Elliott, deputy director of Trust for America's Health, an independent public health organization. "If a community is thinking about closing schools, they're also probably thinking about closing day care centers. And children also depend on schools for a lot of services other than education, including lunch programs and after-school care."
The federal government has taken a leading role in helping states and local communities plan for a public health disaster. Washington's concern grew from the anthrax attacks of 2001 and the 2005 bird flu scare that sparked fears of global infection.
In Congress, the chairman of the House Education and Labor Committee, Democrat George Miller of California, said Wednesday he will hold a hearing next week on how schools and businesses are prepared to handle the swine flu virus.
On a conference call Monday, officials from the Education Department and the Centers for Disease Control and Prevention answered questions from more than 1,400 people from school districts, state education offices and education groups.
Education officials said many asked what circumstances should prompt schools to close. They were encouraged to follow the CDC's recommendation that schools close if they have a confirmed case or if they have a suspected case that is linked to a confirmed case.
In the end, making the decision is a balancing act, not an on-off switch, said Robert M. Pestronk, a former public health officer who heads the National Association of County and City Health Officials.
"Because there is one case in one school, or 10 cases, doesn't lead to a decision to close a whole district," said Pestronk. "It's a case of balancing the risk that is potentially present against the need for communities to operate normally on a day-to-day basis. You're trying to protect people's health and not completely shut down communities."
There may be alternatives to closing schools.
Researchers at Georgia Tech modeled the effects of two options: a voluntary quarantine of affected households in a severe flu, and school closures. They found that both would work about as well.
"It's information that boards of education should consider," said Julie Swann, a professor of industrial engineering who collaborated in the study. "In some cases, you might want to do both kinds of interventions."
Some families are already doing that.
In the New York City borough of Queens, St. Francis Preparatory School closed last weekend and will remain shuttered at least until Monday. The 2,700-student school is the largest Roman Catholic high school in the nation.
Raquel Mooradian and her husband, Greg, have been holed up in their Queens apartment since their 17-year-old daughter, Felicia, a senior at St. Francis, fell ill on Friday. They have two other children, ages 2 and 16.
Raquel said they are afraid to leave the apartment for fear of infecting others. She didn't attend her classes at a local college, and Greg called in sick at his job. However, their teenage son is attending classes at his public school near St. Francis.
When they took their daughter to the emergency room on Saturday night, she had a temperature of 102.7.
The mother said she covers her face so she won't catch the virus when she goes into her daughter's bedroom to bring her soup, water or Gatorade.
"She's able to talk but says, 'Let me sleep, let me sleep,"' said her mother.