Investigations were underway on Monday after mysterious goo and inexplicable marks on the ground were found at King Charles School.
Year five pupils were joined by PCSO Ellie Grey as they pulled on rubber gloves and took out their rulers to examine what was believed to be an alien landing in the school field.
The exercise was aimed at inspiring the children's writing as part of new topic 'to the stars', and as well as the scene on the school playing field - cordoned off with police tape - they were told that there had been similar incidents at other sites round the town including the rugby club and Gyllyngvase Beach.
Class teacher Hannah Sly said: "It's the first day back so after the summer holidays so we have set up this UFO landing.
"It's going to provide inspiration for a police report, then a newspaper report, and witness statements, so it's to support their writing."
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