SCHOOL ended early for Glenmore State High School students yesterday after a bomb threat sent the school into lockdown.

Police were called to the school at 9.45am and students were evacuated from the premises while six officers meticulously searched each building and the school grounds for suspicious devices.

A Queensland Police spokesman said the calls originated internationally.

"We are confident that the calls have come from overseas, and have been designed to cause significant disruption and media coverage. At this time, there is no credible evidence the threats could be carried out here," they said.

"The Queensland Police Service continues to work closely with Education Queensland to ensure the safety of all school children across the state.

"We are also aware of a number of schools in other states and countries having received similar phone calls in the past week."

For one mother, the bomb threat left her chasing after her four kids, unsure where three of them were.

Mitzi Marshall said she found out about the bomb threat over social media and was instantly concerned for her children.

"I heard it all over social media, on Facebook," she said.

"I had been trying to call the school for a couple of hours when a teacher bought my son home, but only one of them.

"I was quite upset that some kids got released and not the others, so I came up here to get the others.'

Ms Marshall said with one child in Year 8, two in Year 11 and one in Year 12, she was frightened when she heard of the threat.

"It's quite scary of course," she said.

"It's very close to home."

But to the teacher who bought one of her sons home, Ms Marshall only had kind words.

"I'm so grateful for her, she freaked right out and bought one of them (her sons) home, so I am so thankful for her," she said.

But Ms Marshall's son Austin Griffiths, Year 12, was less concerned about the bomb threat.

"I got out of class," he said.

It's believed the incident was resolved just before 1pm, with children who had not already been collected by family returning to school at the time.