Police immediately responded to the phoned-in threat but did not find anything suspicious.
“The message from the caller was that there were bombs out in the schoolyard around the school,” police spokesman Einar Johannesen told Stavanger Aftenblad.
The school and the surrounding area were searched but police did not find anything suspicious.
“Based on the work we have done, we don't believe there are any bombs. We can never be 110 percent certain, but we have done the job as good as we can and we believe that the situation is over,” Johannesen said.
According to Stavanger Aftenblad, police left the school just after 11.30am.
The incident came on the same morning that the the British International School of Stockholm was evacuated over a bomb threat.
Around 250 pupils and staff were told to leave the Stockholm school and police and emergency services were called to the scene at 9.44am.
The children, who are all understood to be safe, have been taken to neighbours' houses and a nearby school, a parent told The Local.
Johannesen said that police would look at a possible link between the two threats.
"The threats occurred almost simultaneously. There was about a ten minutes' difference between the the two messages. We will investigate it further," he told Stavanger Aftenblad.
The roughly 550 students at the British International School of Stavanger range in age between two and 16 and come from more than 40 different countries.