Maria Miller, chair of the women and equalities select committee, told school standards and equalities minister Nick Gibb that she was "perplexed" by the government's lack of action since the publication last September of the committee's hard hitting report into sexual harassment and violence in schools.
It revealed that 59 per cent of 13- to 21-year-olds had experienced sexual harassment at school or college in the previous year and made recommendations including legally requiring schools to tackle the problem and for Ofsted to priortise how well schools monitor incidents.
However, these were rejected in the government's response last November.
At a committee hearing today, Miller, Conservative MP for Basingstoke, said that guidance is still too vague and is taking too long to update.
"The committee is perplexed as to why it doesn't appear to have more urgency," she said. "I understand that the education wheels move slowly but we are talking about children being abused in schools on our watch and that has to change quicker."
A particular concern of MPs is that current guidance to schools fails to specify that in cases of peer-to-peer abuse a perpetrator should not continue to be taught in the same classroom as a victim.
MPs are also concerned that in the absence of firm guidance schools are failing to report incidents of sexual abuse to police.
"The lack of a protocol or information or guidance on how you deal with that situation is leaving headteachers flummoxed," said Miller. "I find it extraordinary that young girls are being asked to go back into class with people who have raped them.
"The evidence that we've had given to the committee is that schools do not routinely report these things to police even when they are sexual assaults."
Committee member Jess Phillips, Labour MP for Birmingham Yardley, added that a lack of specific guidance on separating victims and perpetrators in schools was at odds with most other victim legislation.
She added that keeping a rape victim apart from a perpetrator when in a court or health setting "has unpinned pretty much every single victim legislation for the last 30 years".
Gibb said that the government's Keeping children safe in education guidance had been updated last September, adding that ahead of a further update later this year interim advice on peer-to-peer abuse would be issued to schools.
Further advice on protecting children from harm in schools was also issued in July in consultation with expert groups including The Education Trust and Girlguiding UK.
"The guidance cannot anticipate every single possible circumstance that could occur so it is written in general terms," said Gibb.
"Polices at the school should be clear as to how victims of peer to peer abuse will be supported. That to me would include issues of not putting those two children in the same class."