French schoolchildren loose a staggering one billion plus euros (£800million) worth of clothes and equipment every year.
That's around 74€ per child, a substantial dent in the family budget in these cash strapped times.
Among the nearly 1,000 tons of lost items are sports shoes, sweaters, coats and hats as well as books, glasses, transport passes and pens and rulers, according to Scoléo, the school assistance company which carried out the study.
Hardly any lost property is retrieved, meaning that most of it is eventually given away, either to charity or at open days. Some teachers blame today's throwaway consumer culture for this attitude to lost property.
Yet, 'all these losses could be avoided if people put their names and telephone numbers on their belongings,' says Scoléo's Laurent Lescure. 'It would cut down a lot of tension in families.'