Angry parents of boys at an elite Melbourne college have launched a petition to try to stop a change in class times, labelling it “irresponsible”.

On Monday, parents of students at Scotch College in Hawthorn launched the change.org petition, claiming school principal Scott Marsh proposed classes end at 1.50pm one day each week to accommodate “on-the-job staff training”.

“This change would adversely affect students, parents, and caregivers. Boys will now be compelled to take up new interests from a limited range of hobby subjects, engage in co-curricular activities, or leave school early,” the petition reads.

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“Moreover, there will be added pressure on parents and caregivers to adjust their work commitments to accommodate a 1.50pm pickup time for students who do not wish to pursue a new hobby subject.”

As of Thursday morning, the petition has more than 600 signatures, with comments labelling the proposal as “bound to fail” and “irresponsible”.

“As aptly described by another fellow signer, this is a breathtakingly arrogant move,” one disgruntled parent commented on the petition.

Marsh told 7NEWS.com.au in a statement the proposed changes for the 2025 timetable were still going through “consultation with the community”.

He said the afternoon on which the school day would finish at 1.50pm may include an activities program that would end at 3.15pm.

It is unclear if that program would be mandatory for students.

“As part of these proposed changes, we are exploring a new activities program one afternoon per week between 1.50pm and 3.15pm, which may offer opportunities in areas such as the arts, entrepreneurship, technology, lifeskills, sports and more,” the statement read.

“While overall face-to-face learning times have been retained (and in fact increased for several core subjects), pockets of under-utilised time in the timetable have been eliminated to accommodate this innovative program.

“Parents can be assured the college will continue to provide an 8.30am-3.30pm provision for students every day of the week.”

A letter sent to parents and carers last month reportedly said the early finish “would seek to utilise the afternoons for teacher training,” the Herald Sun reported.