One in six young people were already living below the poverty line before the pandemic and are at greater risk of falling behind in their schooling, the charity says.

"Not only has their education been disrupted but their families may not have been in the best position to support their children's home learning," Smith Family chief executive, Lisa O'Brien, said.

Children who fall behind often stay behind as they struggle to stay motivated.

"This in turn affects their desire to go to go to school and our research shows that when attendance slips, so does educational achievement," Dr O'Brien said.

The education gap between 15-year-old students from advantaged and disadvantaged backgrounds is equal to a daunting three years of schooling.

"Sadly, the children who need that extra bit of support to keep up at school are from families who can least afford it, or often, provide it."

Without intervention she warned the impact of COVID-19 on children's education could last a lifetime.

The Smith Family supported about 170,000 children during the past year with extra, out-of-school numeracy and literacy programs.

It hopes to raise $4.2 million to help a further 10,740 children during the coming months.

Funding will go to external programs including Student2Student, which pairs young students with older reading buddies, and after-school clubs.

Many of their traditional programs and mentoring are currently running remotely due to COVID-19, providing structured learning to help ease the transition back to the classroom.

Dr O'Brien says families who receive the charity's support know how important their children's education will be to breaking the cycle of poverty.

She urged people who can to visit the Smith Family website and make a donation before June 30.

Australian Associated Press