Don’t pull that pin!

An elementary school in the UK had to be cleared out, and experts from the bomb squad were called in because a student brought a WWII hand grenade to a show-and-tell presentation.

The school’s principal, Jeanette Hart, said she wasn’t sure if the device was live, but didn’t want to take any chances.

The headteacher, Ms. Hart, described the dramatic incident where she had to act swiftly and calmly. She stopped the assembly, confiscated the grenade from the student, and carefully moved it outside to a safe spot behind a distant tree in the parking lot.

“I wasn’t 100% happy carrying it to be honest.”

The school in Ashbourne, Derbyshire, about 35 miles south of Sheffield, was promptly evacuated and the army bomb squad called.

Army experts deemed the grenade safe by using X-ray equipment.

It turns out the explosive was actually a World War II family heirloom the boy had taken to school without telling his parents.

Hart said she had “a little chat” with the student.

“It was entirely innocent,” she said. “I don’t think he ever really knew what it was.

“He knew it was from the war and just thought it was an interesting thing.”

She said the boy’s parents “were a little taken aback” when they found out what their son had been up to.