As Gordon Brown debates reclassifying the “killer weed”, hundreds of secondary pupils in Portsmouth have ditched Bunsen burners in favour of high-tech equipment police found in the city at an abandoned cannabis factory.

They found 160 plants which could have yielded cannabis worth pound;30,000 on the street and lighting equipment used to help it grow that is worth thousands.

“Normally the equipment would be destroyed,” Sergeant Jim Stewart said. “But two of my community support officers came up with the idea of donating it to local schools.”

At City of Portsmouth girls’ school, leaves are already sprouting under the powerful lights. A spokeswoman for Portsmouth council said she was not sure what the girls were growing, only that it was green and it was not cannabis.

Sheena Wright, head of science, is grateful for the gift and has already used the equipment to explain photosynthesis and to give a fresh perspective on drugs education to her pupils.

“We are glad to be able to help the community by legitimately using proceeds of crime for educational purposes,” she said.

A set of lights has also been despatched to the Spinnaker Centre, a pupil referral unit in Fratton.

Derek Bell, chief executive of the Association for Science Education, said the police action was a useful way for schools to get equipment they couldn’t otherwise afford but warned that the lights would need stringent safety checks.

“Given it’s been used for growing cannabis, let’s hope it doesn’t include instructions as well,” he said.