Among the phone calls was an automated message saying that an explosive device could be on school premises and that students might be harmed.
At least 12 schools in Victoria were evacuated, including at least 10 primary schools, while police also responded to incidents in schools in New South Wales, Queensland, Tasmania, the ACT and South Australia.
At several threatened schools in Victoria, emergency procedures were put into practice at around 10:30am with students removed from buildings, according to Victoria Police. Some schools had received the threatening calls directly, while others located close by evacuated as a precautionary measure.
According to Fairfax, some Victorian parents were not informed of the threat for several hours, despite a promise earlier this year from Emergency Minister James Merlino to fund an instant SMS service to alert parents immediately of such emergencies, following complaints regarding the communication of a similar hoax threat in February.
One parent, Corinna Berg, whose child attends Black Hill Primary in Ballarat, told Fairfax that she only heard about the threats on the news, but praised the school for keeping students "really calm".
Another parent, whose children attend Cambridge Primary School in Melbourne, was more critical of the handling of the evacuation.
"We would have expected to be notified earlier. I understand there is a fine balancing act, but it would have been nice, when your children are there [at the school], to be told if they are being taken off school grounds," he said.
Commenting on the delay in contacting parents, Education Department spokesperson Craig Simon said, "In situations like this, schools' immediate focus is on enacting their emergency management plan and working closely with police, so that children and staff are safe".
"Schools contacted parents as soon as they deemed appropriate, after enacting their emergency management plan."
No group has yet come forward to claim responsibility for the latest hoax calls. The comparable phone threats in February were subsequently claimed by an international hacking group calling itself the Evacuation Group. Following the hoax, the group gave its reasons for its actions in an email exchange with Fairfax Media.
"One, they are entertaining for us; two, we make money off them sometimes; and three, just for the mayhem of it," said the group.
A number of schools across Australia and New Zealand were forced to evacuate on Thursday after they received threatening phone calls.