The Education Department has started placing relocatable classrooms on the school's grounds as a replacement for rooms that are not considered safe.

But Wyndham residents have questioned whether enough work has been done to ensure the school is ready for students to return next month.

Hundreds of parents have also signed petitions calling on the government to make up for years of "neglect" and rebuild the school, which was closed late last year after a roof collapsed.

Black mould was also discovered in some classrooms as entire year levels were instructed to take days off or were bussed to nearby schools.

Charlotte Hughes, whose eldest daughter completed year 12 at Galvin Park last year and whose son will start at the school in year 7 next year, said the relocatable classrooms were a suitable short-term solution as long as affected rooms remained closed.

Ms Hughes believes the problems at the school impacted on her daughter's VCE results, and she doesn't want to see this year's students also affected.

"My daughter became stressed because she had to move classes and she suffers from asthma, so the damp and mould affected her breathing during the exams," she said

"She really felt it impacted on the outcome of her exams. Everyone's grades would have been down because of what happened."

Ms Hughes is campaigning for the government to commit to rebuilding the school to ensure its buildings are safe in the long term.

A department spokesman said the school would be clean, safe, dry and ready for classes on the first day of the school year. The school would be in contact with parents before the first day of term to provide an update on works that have taken place over the holiday break, as well as outlining what would happen in the coming term.