Teenage girls' diaries have been used to help convict a former PE teacher of sexually assaulting five pupils.
Richard Hilary, 67, was found guilty of 14 counts of indecent assault against the girls, who were under 16 at the time, while working as a teacher and sports coach in Hampshire.
His trial heard he gave the girls massages and took baths with them before assaulting them.
Hilary was jailed for 15 years, with one year's extension.
Winchester Crown Court heard the attacks took place while Hilary was working at the Wavell School in Farnborough and at Winchester Athletics Club in the 1970s and '80s.
He would take the girls to secluded beauty spots where he asked them to perform sex acts on him, the jury was told.
The court also heard he told one of the girls: "You're better at it than with my wife."
Some victims kept diaries of the assaults which recorded "smoochy dances" and Hilary's request for "Christmas kisses".
Following sentencing, Rob Welling, from CPS Wessex, said: "Hilary was described by many of his victims as a popular and dynamic teacher, a fact he exploited as he groomed the girls into performing sexual acts for him.
"The CPS was able to use the teenage diaries of his victims which made clear Hilary's crimes at the time they happened and provided compelling evidence to put before the jury."
Senior investigating officer Det Sgt Gemma Hunter said Hilary "grossly abused his position, knowing full well the impact it would have on the girls".
She added: "I hope that today's conviction and jail sentence gives others who have suffered abuse of this nature the confidence to report it to police."
Hilary, of Northend Lane, Droxford, went on to become headteacher of Chamberlayne Park School in Southampton and retired aged 55 in 2006.