Every month, five-year-old Sasaki dons her padded bonnet for her regular earthquake drill and ducks down below her desk. But now, it seems, her Tokyo school's best efforts might be in vain. A government report has revealed that in this tremor-riddled land, less than half of Japan's 150,000 school and universities are sufficiently earthquake resistant.
With no way of telling which schools are at risk - the government has not supplied a list - Erika and her parents do not know whether she will be safe if the next "big one" strikes during school hours.
Experts say that Tokyo in particular is overdue a large quake, of the same or bigger magnitude as that which killed 6,000 in the Great Hanshin earthquake of 1995 in Kobe. Seismologists warn there could be a repeat of the 1923 Great Kanto quake which killed around 140,000 people and measured 7.9 on the Richter scale.
New buildings have to be able to withstand a quake measuring 7 on the Japanese intensity scale - top of the range - to meet minimum requirements.
But for many of the country's crumbling schools it is an unachievable safety level.
Kobe's quake, which registered a 7.2 on the Richter scale, measured only 3 on the Japanese scale. Some experts are expecting a force 6 or 7 quake to hit the Kanto region any time now. If that happened, half of Tokyo's schools would simply disintegrate.
There are other concerns, too. Two-thirds of city schools have no nearby evacuation spaces - such as children's playgrounds or parks.
Boards of education have repeatedly requested more money to rebuild Japan's now mostly decrepit schools. But with a stalled economy, most have made do with refurbishing which does not extend to costly earthquake-proofing.