An average of one child in every classroom goes to school or bed hungry nearly every day, while one in five say this happens sometimes, a study of Australian children shows.

Key points: 5,000 children surveyed across Australia

5,000 children surveyed across Australia One in five children reported having gone to school or bed hungry

One in five children reported having gone to school or bed hungry One in six said they had been bullied

One in six said they had been bullied Support networks important in affecting how children perform in school

The survey of more than 5,400 children in schools across Australia also showed one in 10 children missed school at least once a week and one in six said they had been bullied.

The lead researcher, Flinders University's Associate Professor Gerry Redmond, said the Australian Child Wellbeing Project (ACWP) findings showed that for many children "life is pretty tough".

"One young person in five reported going to school or bed hungry at least sometimes, and were also more likely to miss school frequently," Professor Redmond said.

"What we really want to bring out with this is how hunger is linked with a whole load of other issues that impact seriously on a young person's wellbeing," he told 666 ABC Canberra.

"Hunger itself is a big wellbeing issue but it's also linked to other issues that policy markers are also very concerned about - such as engagement at school, missing school all together and bullying.

"Young people who go hungry are more likely to experience these other issues and problems."

Survey focused on 'missing middle years'

Professor Redmond said the two-year study began in 2012 and was the largest of its kind in Australia, in which young people were the informants.

He said the survey focused on the "middle years" between early childhood and adolescence, when children were aged between eight to 14.

"The only national research that's carried out on young people in the middle years is really relating to academic achievement," he said.

"You've got NAPLAN carried out in years three, five, seven and nine. You've got some international studies in years four and eight, but you don't really have any other large-scale information on young people's development in this period."

Professor Redmond said the study did not focus on a particular area, or demographic, but did find that if young people were marginalised, or were economically disadvantaged, were "missing out on opportunities that should be available to all young people".

"Support [also] makes a big difference," he said.

"If you feel like you're supported by your teachers, if you feel like you've got a large network around you, then regardless of your economic circumstances, you tend to assess your life as better than if you don't have these things.

"Where they have support networks they can draw on... they tend to perform better in school and be more motivated in school."