Jack Strickland fell at least 10ft from the roof of a unit at Derwent Works, in Matlock Road, Ambergate, on April 9.
The 19-year-old was taken to hospital but later died.
Dick Vasey, headteacher of Ashfield School, who taught Jack personally, described his untimely death as “so tragic”.
Mr Vasey said: “Jack was a hard working, mature and very polite student.
“He was a very popular student who had excellent relationships with both staff and students during his time at the school.
“I taught Jack myself in Year 11 and he was always eager to please, cooperative and a pleasure to teach.
“His untimely death is so tragic and the whole school community’s thoughts are with Jack’s family at this sad time.”
Jack was also described as a “true gentleman” by colleagues at Wilstec Engineering, where he was completing an apprenticeship.
A spokesman for Willstec said: “He was the model apprentice and a true gentleman. Nobody had a bad word to say about him. It really is very sad.”
A spokesman for Derby and Derbyshire’s Coroner’s Court said an inquest had opened into his death.
He said a provisional cause of death for Mr Strickland, of Sutton, could not yet be given.
It was initially reported by the emergency services that the teenager died after falling from a roof in a derelict part of the site but police now say the incident happened in an occupied unit - but will not confirm which one.
At the time of the incident, a spokesman for the police said there were not thought to be any suspicious circumstances behind the death.