Egg-cellent fun was had at Gosberton Academy, when mysterious eggs were discovered.
One was found on a tree in the grounds, and the other was on the roof of the building.
The egg’s arrival was all part of a scheme to encourage children from reception to Year 6 to write.
Jamile Sherrick, head teacher at the school,said: “We did it to generate good writing from the children.
“They spent the whole week writing about the egg and then what is in it - some children thought it was an alien and some thought it was a dragon.
“Then we called the CSI team and the fire brigade who cordoned the area off and examined the egg.”
The children who wrote the best stories - judged by school governors - will receive prizes at a special awards ceremony next month in Boston, which will be a red carpet event attended by children’s author Steve Bowkett.