Wildlife presenter Chris Packham has called a Hertfordshire school's action in trying to get rid of a fox "absolutely disgusting".
Richard Whittington Primary School in Bishop's Stortford spent nearly £2,000 on a "specialist contractor" after the animal was seen in its grounds.
The school said it posed "minimal threat" but it was "erring on the side of caution".
Mr Packham said it was a missed opportunity to learn about wildlife.
The Springwatch presenter said: "This is a unique opportunity for young people to engage with wildlife first hand.
"They could easily be managed by the teachers and told not to approach the animal and simply to enjoy it.
"To think they are to be taken out of the school, at any expense whatsoever, is frankly disgusting."
A spokesman for the school said Mr Packham was entitled to his opinion.
A statement said it was a "safety and hygiene issue" and safety of the pupils was its "primary concern".
"We have liaised with and taken advice from local authorities, including environmental health and the RSPCA," it read.
"Following this, control measures have been put in place by a specialist contractor."
The school told parents the contractor had cost £1,870 so far, but said the fox "is still visiting".
"We are taking further advice from relevant professional bodies," it said.
Mr Packham said it showed people were "susceptible to the most ludicrous scaremongering that our society can muster on behalf of an animal".
"We know that every year there are 6,000 cases of dog bites treated in hospitals at the cost of £3m to the NHS and on average one adult and one child dies in dog attacks each year in the UK," he said.
"I am absolutely certain that if it were a dog then this action would not be happening."
Two local authorities said they had no record of a call from the school.
John Troup at Uttlesford District Council said its general advice is that if a fox is not causing a problem then "leave it alone".