New entry requirements for the Junior College should be suspended until they are properly discussed, the Malta Union of Teachers said on Thursday.
It called on the government to suspend the legal notice that bring the new rules into force.
The new rules mean applicants to the Junior College will no longer need three passes in the core subjects - Maltese, English, Maths - although they will be required to achieve them before moving on to the university.
The union said the changes had been made without consultation, and they needed to be considered thoroughly and consensus sought.
The union said it has already communicated with the Rector at the University of Malta and the permanent secretary at the Ministry for Education about the issue following queries and objections received from members.
Meanwhile, the Nationalist Party said it was incredible that the entry requirements to the Junior College were changed a few days before the general election, without any discussion or consultation.
Such a decision could not be taken for partisan reasons, and if this was another attempt to win votes, then Labour was sinking to a new low in an attempt to grab more power, the PN said.