Dyke House Sports and Technology College in Hartlepool unveiled its new open-plan loos on Tuesday after a £12.4m transformation.
The toilet blocks are for girls AND boys, and have three floor-to-ceiling cubicles.
The facility's design means that boys and girls exit the cubicles and use sinks in the same room.
The school was remodelled under the Building Schools for the Future (BSF) programme, but its modern design has not gone down well with some parents.
Speaking to the Daily Mail, mum-of-two Lynsey Smith, 32, whose son attends the school, said: "If I had a daughter I wouldn't like to think you have got boys there giving it 'howay', carrying on while the girls are going through periods and all that sort of stuff. And if people are dating they might end up in the toilets. It's asking for trouble really."
Other concerned parents took to Facebook to vent their anger at the new conveniences, with one mum claiming her daughter was "refusing to go to the toilet for the next four and a half years", adding that she had contacted Hartlepool Borough Council and her local councillor over the matter.
The school said the new loos are "the way forward in 21st Century schools" and insisted the block will always be monitored.
Headteacher Andrew Jordon said only two parents had raised concerns about the toilets and even they had changed their minds once they had been given a tour of them.
He said: "What we had at the old Dyke House was girls' and boys' toilets in the same block, but with a rat-run of places where people could smoke.
"We have got them contained within the same block, but it's much more of a pleasant experience. The toilets are very separate - they all have individual cubicles which have floor-to-ceiling doors. There will be a set of toilets for each individual year group that have three individual cubicles for boys and three for girls."
What do you reckon?
Good modern facilities, or a completely inappropriate for a mixed school
More:Advice And Health
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