Unisex lavatories - with blurred glass walls - could help in the battle against school bullies, government guidelines for England suggest.
The recommendations for new secondary schools also include putting toilet blocks close to staffrooms or offices for subtle supervision.
If the ideas are taken up, urinals would be a thing of the past and privacy would be protected.
Campaigners say crumbling facilities damage pupils' health and well-being.
They say school toilets are recognised as being a trouble-spot for bullying, with some children avoiding going, possibly leading to continence problems.
I don't want my head dunked down the toilet
Pupil's complaint to campaign group
The recommendations cover schools being rebuilt or refurbished under the government's £45bn Building Schools for the Future programme.
Tim Byles, chief executive of the Partnerships for Schools, the agency responsible for the programme, said behaviour could be improved by good design.
"Toilets are recognised as a hotspot for bullies to threaten and intimidate others," he said.
"This is clearly unacceptable. The new standard specifications for toilets in schools means that cramped, dirty and vandalised toilets can become a thing of the past.
Central sink troughs
Must be kept clean
"Toilets in BSF schools will no longer provide bullies with places that lend themselves all too readily to anti-social behaviour."
It is suggested that making toilets unisex would discourage pupils from congregating in the area.
The guidelines received a warm welcome from the charity Education and Resources for Improving Childhood Continence (Eric).
The charity's Bog Standard website - which campaigns for better facilities - includes complaints from many children about dirty, threatening environments.
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JJ, aged 13, from Swansea, wrote: "I dont like using my toilets. There are always people in there smoking, and they are bullies. I don't want my head dunked down the toilet. When there aren't bullies or smoking in there, they smell, they are dirty, and have no locks".
Jessca, aged 13, from Warwickshire, wrote: "The toilets at my school are terrible they smell there are no seats and no loo roll and no locks on the doors and even no chains because the school cannot be bothered to fix them they have been fixed before but not in the last 6 months and the loo's have not been open for over 4 months ther is over 1300 students at our school and 1 toilet open".
Simon, 13, from South Yorkshire said: "My school toilets stink and are never properly cleaned. People block up the sinks with toilet paper and because the taps are broken they stay on and flood the toilets.
"They also wet toilet paper and throw it everywhere. The locks on the doors don't work and people can open them from the outside so there is no privacy".
Beverley Leeson from Eric said: "We are very glad that the guidelines have been produced.
"It's a huge issue for pupils and if they are holding on because they don't want to use the toilets or because they aren't allowed to go, it can cause health and well-being problems.
"Some adults think it's not a big issue and say 'we always had terrible loos at school too' but that's no reason for things to stay the same".
There is no legal requirement about the standard of toilets at school beyond a certain ratio of lavatories and wash basins to pupils.
Employers, however, have a legal obligation to provide clean toilets with privacy plus sinks with hot and cold running water.