In return, Ms Bennett accused Labour's Jacinda Ardern of not being in the real world, saying that measures of poverty would be speculative and the circumstances of any child could change quickly.
The exchange happened after Ms Ardern asked Ms Bennett about official measures of poverty and whether she agreed with the green paper on vulnerable children which stated that 20 per cent of children lived in poverty.
Ms Bennett said there was no official measure of poverty and any measure was likely to be speculative because it was constantly changing.
After Labour MPs scoffed at her claim that children could move in and out of poverty "on a daily basis", Ms Bennett told them to "get in the real world".
"One week they can be in poverty, then their parent can get a job or increase their income and they are no longer in poverty ... This is the real world, and actually children move in and out of poverty at times on a weekly basis."
Ms Bennett said the Government was focusing on addressing poverty rather than measuring it, and so was putting its efforts into other areas.
Ms Ardern said later that Ms Bennett's refusal to measure child poverty showed she did not want to admit the scale of the problem, or was afraid it would show a failure to deal with the problem.
The Opposition also continued to criticise Ms Bennett for refusing to apologise for releasing the benefit details of two single mothers in 2009, or to rule out taking the same action again.
Labour's Grant Robertson said ACC Minister Judith Collins took a hard line on accidental privacy breaches within ACC but the Government was condoning a deliberate release by Ms Bennett.
A privacy complaint against Ms Bennett by Natasha Fuller was resolved this week and the Director of Human Rights Proceedings announced no proceedings would be taken.
However, it was made clear he believed there was a privacy breach - something Ms Bennett continued to reject yesterday. Standing in for the Prime Minister, Gerry Brownlee said that there had been no finding of a breach of privacy and the matter had been settled.
Asked by Green co-leader Russel Norman what circumstances would warrant a Government minister releasing personal information without consent, Mr Brownlee said he would not answer hypothetical questions.
"What I can say is that when it comes to people like Stewart Murray Wilson [the "Beast" of Blenheim], the public expect those details to be in the domain. Therefore, it is a very difficult question to answer specifically."
Ms Bennett had argued in 2009 that releasing the income details of the two women was justified to ensure the public was fully informed after the women publicly objected to scaling back the Training Incentive Allowance.
- Claire Trevett and Kate Shuttleworth