Parents who face £130-a-day fines for dropping their children off outside school have slammed the council scheme.
Croydon Council in south London is running the six-month trial outside three schools in the area, in which parents cannot pick up or drop off outside the school.
The trial takes place outside Woodcote Primary School in Coulsdon, Heavers Farm Primary School and St Chads RC Primary School in nearby Selhurst.
The council says it has signed up to the scheme because of its "concerns about parking and pedestrian safety".
Yet the move has angered some parents who warn they now face crossing busy roads with their children and claim that the already busy streets surrounding the schools could become dangerous.
Georgiee Rodriques has two children at Woodcote Primary - Savanna, five, and Tallie, two, and lives three miles from the school. The journey would mean a two-hour walking round trip.
This will make the school run really difficult, I have two kids and the road is really busy.
It is understood that teachers at the schools and nearby residents will still be able to park close to the schools without being fined.
Those not allowed into the banned zones will receive a £130 penalty charge notice, or £65 if paid within a fortnight.
Chloe Westley of The TaxPayers' Alliance said Croydon Council "ought to explain to parents why they think this punitive measure is appropriate when they are already increasing council tax by more than four percent this year."
But Councillor Stuart King said: "These roads are a school run traffic headache for everyone, so this trial is about improving child safety and boosting walking and the environment."