About 70,000 children in Scotland are on social housing waiting lists, according to new analysis from Shelter Scotland.
The figure amounts to 20 children in every school.
The charity is calling for at least 37,100 social homes to be built to help tackle the issue.
Housing Minister Kevin Stuart said the impact of lockdown had resulted in a "necessary pause" in the delivery of affordable and social homes.
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One mother in Dundee told how she had been waiting for a home with a social landlord such as a council or housing association since before her son was born – he is now aged two.
She and her boyfriend previously lived at his parents' home but found the living situation a struggle and "rushed" into a private let.
While they both work, they still find the cost of private rent a "constant struggle".
'The landlord could just drop us'
"Affordability is a massive, massive thing," she said. "In the private sector you're paying their mortgage and some more.
"If we could get a social tenancy the worry wouldn't be there that the landlord could just drop us and put us out because they want to sell."
The Shelter Scotland analysis of the Scottish Housing Survey indicates there are about 40,000 households with children on waiting lists for social housing, and about 70,000 children within those households.
In a YouGov survey commissioned by the charity, knowledge of the number of school children on social housing waiting lists increased support for building more of these types of homes.
- 55% of respondents believe the next Scottish government should build more social homes than the current government will have built by the end of this parliamentary term
- This figure increases to 65% when those surveyed were provided with the analysis of the number of children on waiting lists
- 4% believe the next Scottish government should build fewer social homes
- 63% believe Scottish political parties should prioritise building social homes
- 21% believe they should prioritise ensuring more people can buy homes
The poll of 1,073 adults in Scotland was carried out between 8-11 September.
'It's not right'
Shelter Scotland director Alison Watson said: "It's not right that tens of thousands of children don't have the security of a safe, affordable home.
"We know that delivering more social homes will support economic growth, create jobs and help Scotland to meet its climate targets.
"It will also strengthen our communities – reducing poverty and inequality, improving people's health and tackling the root cause of homelessness."
Housing Minister Kevin Stewart said: "We are committed to expanding our social housing stock and have transformed access to affordable housing.
"The impact of lockdown meant that there was a necessary pause in the delivery of affordable and social homes at a critical time in our 50,000 target period.
"We are continuing to work with partners across the housing sector in order that the programme can be progressed, as construction resumes in a new safe way."