A teacher revealed she ran to get help after a young homeless mother called her, contemplating suicide.
The Dublin teacher also said she had washed pupil's clothes because parents had nowhere to do laundry in hotels or B&Bs.
It comes as the Irish National Teachers' Organisation (INTO) highlights how badly teachers are "struggling to cope" with child homelessness.
The teacher spoke to the Irish Independent under condition of anonymity, but revealed her ire at the Government's "failed housing policies".
"I'm at the end of my tether," the Dublin teacher said.
"I had a mother of four children call me, telling me that she couldn't take anymore.
"It's breaking my heart every day. I ran to the hotel and let a social worker know. I sat with the mother and made sure she got support but I can't do this anymore."
The latest child homeless figures provided by Barnardos show 3,829 are without a stable home.
The INTO is calling for immediate action to calm the situation in classrooms due to mass child homelessness.
"Homelessness is an educational crisis too. More than an entire primary school class, 35 pupils, became homeless every two days in February of this year," Sheila Nunan, INTO general secretary, said.
"Teachers are growing increasingly concerned the lack of a proper and stable home is harming children's education.
"School children who are homeless are often seriously struggling in school while their teachers struggle to help them to cope."
A Department of Education spokesman said: "A range of resources are available to support schools in dealing with identified additional educational needs, including needs which may arise for children who are experiencing homelessness. Supports for schools are also provided by Tusla's Educational Welfare Service and by the Department of Employment Affairs and Social Protection."