A proposal to ensure excluded pupils are not on the streets is unworkable, according to charities which help parents with education matters.
Exclusion should not be a "holiday", ministers say
The government's education bill would criminalise parents in England if their children were seen in public after they had been excluded from school.
Parentline Plus and the Advisory Centre for Education say this could even mean parents and carers losing their jobs.
The Department for Education said parents had to tackle bad behaviour.
The bill would make it an offence, punishable by a fine, for excluded children to be seen in public during school hours.
"This imposes the potentially huge burden on parents and carers of confining their child inside the home during school hours," the charities said.
"Some of these children are bigger and stronger than the parent who must confine them or risk a fine."
They say the likely effect is that parents who are in work, taking up training or seeking work - perhaps as a way out of poverty - run the risk of losing their jobs if they have to "drop everything" to supervise their children.
"Exclusions of up to five days are not challengeable by parents and nor will governors review the exclusion.
"Yet, unless the parent ensures that the child remains indoors during school hours for the whole period, in effect house arrest, they are liable to a heavy fine even where it is the school's relationship with their child which is to blame."
The two organisations say money spent on implementing the sanctions would be better spent on agencies trying to help "vulnerable families".
The Department for Education and Skills said the bill underlined parents' responsibility to tackle their children's bad behaviour.
"But parents will not necessarily have to stay at home with their children while they are excluded," a spokesman said.
"The offence will be failing to ensure that their child is not present in a public place during school hours without a reasonable excuse such as a pre-arranged doctor's or dentist's appointment."
Meanwhile, England's teaching regulatory body has also come out against the government's education bill.
The General Teaching Council for England said the priority ought to be addressing underachievement and educational disadvantage.
But it did not believe the bill, in its current form, would achieve this aim.
It has proposed a series of changes stressing collaboration between schools and fairness for all children.
The Education and Inspections Bill got over its first major hurdle in the House of Commons last month but 52 Labour backbenchers rebelled and another 25 abstained.