The day was held to commemorate Muscular Dystrophy Australia's national awareness week, which involves people hosting Super Hero days during the first week of September.

Holy Rosary had a special reason for commemorating the week - prep student Ryan Healy was diagnosed with the disease in January this year.

The school tied in Superhero Day with Book Week, so students dressed as literary characters and superheroes.

Parents Charlotte and Michael Healy said they were happy the school was educating students about the disease. 

"They're starting a conversation about the disease, not hiding it," Mrs Healy said.

The couple said they were still coming to terms with Ryan's diagnosis, a devastating discovery.

"It will be an ongoing grieving process," Mr Healy said.

"By the time (Ryan) finishes primary school he will need a wheelchair."

Muscular dystrophy is a genetic disorder that involves people's muscles progressively breaking down, severely restricting their mobility.

While there are different strands of the disease, Ryan has duchenne muscular dystrophy, which affects boys. 

It can cause heart and lung problems and most patients only survive into their 20s. 

Mr and Mrs Healy said Muscular Dystrophy Australia had been a great point of contact since Ryan was diagnosed.

They said the Royal Children's Hospital had also been fantastic, with Ryan seeing six specialists there every three to six months.

They said they wanted to increase awareness about the disease and be ambassadors for families in Bendigo affected by it.

"We want to make people realise how serious it is," Mr Healy said. Proceeds raised from super hero days will go towards research to help find a cure.