Youngsters at Hellesdon High School had to walk in the road on their way into school after work in Middleton's Lane blocked the entire path.
It is believed City Fibre have been carrying out the work throughout the holidays but it overran.
Worried parents took to social media to share their anger about the children having to wander into the road in order to get to school.
Many pleaded with drivers take extra care along the road to avoid any accidents.
Alison Milne has a child at the school who is currently in year seven. Her child was among countless that had to edge their way along the road to get to the school gate.
Alison said: “I recently spoke to someone from City Fibre as I had massive concerns over how they had worked around Woodland Road area and how dangerous it was for the children.
“I have a child at the high school that has to cross Middleton's Lane and with no island in use at the minute as well, it's so dangerous.”
Lisa Jayne has a child in year seven at the school and is disgusted this work wasn’t completed during the holidays.
She said: “When my son got home, he said it was so bad and that a child almost got hit.”
Hellesdon High School headteacher Mike Earl was equally shocked to see the work had not been finished.
He said: “Our site manager had been assured that these works would be completed by the start of the new term.
“Clearly this is not the case and this morning I spoke to the company carrying out the work to raise the significant health and safety issues for our students and indeed motorists using Middleton's Lane.
“They have assured me that the works will be completed in the next 24-48 hours.”
Chris Alston, highway area manager said: “This work being carried out by a utility company was due to be complete over the school holiday.
“We have visited site and can confirm the path should now be open as usual.”
City Fibre has been approached for comment.
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