The youngsters made the grim discovery in the Springburn area just north of the city centre, yesterday afternoon.
Police are treating the death as suspicious and are trying to piece together exactly what happened.
Officers were called to premises in Cowlairs Road at around 2.30pm after the grisly find.
The body, thought to be that of someone aged in their 30s, has yet to be identified.
Detective Inspector Brian Dodd, who is leading the investigation, said today: "Checks are being carried out, including looking at missing person reports.
"A post mortem is expected to take place today but the death will be treated as suspicious meantime."
Officers were standing guard outside the former bike centre following the discovery.
Today the disused site, which includes a car park, was cordoned off while Cowlairs Road was close to its junction with Millarbank Street.
The building was formerly J Harley's Rider Training Centre, but it is understood to have closed around two years ago. The area around it is now overgrown and entrances are blocked.
Police said although the woman's body was found in an isolated area, they are urging anyone with information to come forward.
DI Dodd added: "I would ask anyone who frequents this area and saw anyone or anything suspicious to come forward.
"Extra patrols will be placed in the area."
The street leads to a Network Rail maintenance site and is not a through road.
One worker employed by a firm nearby said: "Unless you were heading to the rail depot there wouldn't be any reason to head in that direction.
"It is horrible to think that a body has been found there."
Anyone with information should call 0141 532 4116 or, anonymously, on Crimestoppers on 0800 555 111.