Stephen James Foster, 18, of Walls Crescent, Hamilton, pleaded guilty to burglary, theft and going equipped to steal.

Hamilton Magistrates Court heard Foster and a co-accused climbed through an unlocked window at Baimbridge College about 10.20pm on November 3 last year .

The pair took a blanket from a cupboard and jumped from an open window to the ground, with Foster later telling police he planned to go swimming and needed a towel.

On November 28 he was spotted in central Hamilton pushing a bike that had been reported stolen.

Defence counsel Noel Kennedy said his client had been living with friends when the offences took place and had since moved back in with his parents and was pursuing education and training.

Magistrate Jonathan Klestadt told the teen: "This has the potential to be a millstone around your neck for the rest of your life."

Mr Klestadt chose not to convict Foster but imposed an aggregate fine of $500.