The number of homeless students in the US is the highest in more than a decade according to a new study.

The report by the National Centre for Homeless Education showed most of the 1.5 million homeless schoolchildren stayed with other families or friends after losing their homes.

But 7% lived in abandoned buildings or cars.

It is often caused by job insecurity, unaffordable housing, domestic violence and recently the opioid crisis.

Living without a fixed address has a seriously impact on children's education and health.

Less than a third of homeless students were able to read adequately, and scored even lower in mathematics and science, the report showed.