Parents have launched a petition claiming a school's 'loo ban' is forcing children to choose between going to the bathroom or having lunch.
Lightcliffe Academy has sparked an angry backlash after it banned toilet trips during the day, resulting in huge queues at break time.
This has led to a flood of complaints, with a petition now calling for bosses to reverse the policy.
The school in Halifax, West Yorks., has taken the decision to restrict students’ access to loos and enforce a toilet timetable of lunch, breaktime and before or after school.
It says students are encouraged to go to the toilet outside of class time to avoid disruption to lessons.
But parents have slammed the move and branded it "oppressive".
Joanne Harney, whose teenage daughter attends the school, said: "It's totally oppressive. They're almost having to decide between going to the loo and eating."
Pupils can be granted 'toilet passes' which allow pupils to use the disabled toilet if in desperate or urgent need.
But these only allow them to use one disabled toilet in the school's reception, which becomes busy.
Around 100 people have signed a petition and are demanding the school reverse their decision.
Nicola Hanson, who has two children at the school and started the petition, said: "I think it's wrong on so many levels. It's really awful.
"It's totally counterproductive, has a negative impact on healthy habits - including drinking lots of water which improves concentration - and increases UTIs and other bowel and bladder issues."
Nicola said girls can't always predict when they will need to use the toilet if they are on their period.
And she said explaining to a male teacher why they need a toilet pass might cause embarrassment.
She added: "It means those who do genuinely need the loo take longer time away from lesson as they have to ask permission and queue at the now very busy single disabled toilet.
“Making them walk past locked toilets to access a disabled toilet and join a longer than necessary queue is my main point of complaint."
Another parent, who wished to remain anonymous, said: "My daughter ends up going to the toilet before school at 7.30am and then doesn't go again until 3.45pm.
"At lunchtime, she has to either queue for the toilet or go to get something to eat. She can't do both."
Head of School, Roz Wood-Ives, said: "In common with many other secondary schools, our policy is that students are encouraged to go to the toilet outside of lesson time to avoid disruption to lessons, unless they need to for medical or health reasons, or it is an emergency.
"Students who need to use toilet facilities in an emergency have access to them in the main foyer during lesson times.
"Due to the positive relationships that exists between staff and students, staff use their discretion to ensure that those who genuinely need to access toilet facilities feel comfortable in seeking permission to do so.
"We have recently invested £10,000 in improving our toilet facilities, and have had positive feedback from students on these improvements.
"However, we are aware that some students and parents are unhappy with these arrangements, and are actively working with our parent and student councils around how we can address their concerns."
