Parents hoping for a trouble-free summer holiday were alarmed to receive letters from the county police inviting them to report, with their young sons, to their local station.
The force is desperate for 10 to 13-year-olds to take part in an identity parade involving an alleged persistent offender who looks younger than his 15 years.
"These will be our youngest-ever volunteers," says Inspector Andy Plant, head of Nottinghamshire's identity suite. "Obviously we're used to holding ID parades but until now we've only ever had problems recruiting people over 75."
But parents can be reassured that their offspring will not have to rub shoulders with ne'er-do-wells as police have turned to video technology.
Volunteers are filmed individualy at the station, and the suspect is added to a compilation of moving mugshots which is then screened for the witnesses.
But officers have been trying to complete the line-up for more than a month.
Letters have gone out through city schools, and last week an appeal was published in the local paper. So far nine candidates have come forward.
Volunteers need the agreement of their parents, who must accompany them at the line-up.
The county's usual fee for joining a line-up is a crisp tenner, but in these days of market forces, a shortage has driven up the price.
In other words, children can do their civic duty and learn a useful lesson in economics at the same time.
Police are looking for mixed-race boys aged 10 to 13, between 4ft 10ins and 5ft 4in and with short black hair. Parents should contact Carlton police station on 0115 844 6924.