Parents of pupils at Britain's biggest Jewish school are to pay for private buses following a series of incidents on public transport.
In one attack last week, a gang threatened to stab a JFS pupil travelling home to Golders Green, North West London.
The attack, which included the boy's friends being called "Jewish pigs" and "scum", follows the throwing of stones at bus windows and antisemitic taunts shouted at youngsters.
Parents have now arranged for a private coach, which already travels to the school from East London, to make an additional stop in Golders Green for youngsters who are now too frightened to catch public buses. It costs around £70 a month for each pupil to use the private service, which currently carries 80 children.
JFS headmaster Jonathan Miller said the incident, on Monday last week, had been taken "very seriously" and that staff had given pupils advice on keeping safe outside school grounds.
The school has 2,000 pupils and is thought to spend more than £130,000 a year on security at its site in Kenton, North West London.
Community Security Trust figures show there were 31 attacks on Jewish pupils travelling to or from UK schools last year.
Denis MacShane MP, who chaired the 2006 All-Party Parliamentary Inquiry on Antisemitism, said: "The attacks underline the need to tell, not hide, the truth about new antisemitism which poisons minds, to the extent that attacks on Jewish children in North London can take place.
"The Jewish community has already had to spend millions to protect its buildings and events. Other faiths do not have to find this cash and the government must accept the arguments advanced by our report that this is a real and not made-up problem."
The father of the boy who was threatened said it had not been an isolated incident.
"A gang gets on the bus in the same place most days and then goes upstairs and threatens the Jewish boys and girls," he said.
"Everyone on the bus was terrified. The gang also kicked a Jewish boy after they saw his uniform."
The 183 bus route is operated by Transport for London and travels from Pinner to Golders Green, via Kenton.
JFS parent Nikki Scheiner has now made arrangements for her 15-year-old son and 13-year-old daughter to travel home to Golders Green on the private bus.
She said: "Our children are scared. They are sitting ducks because of their uniform."
Dr Scheiner said her son had previously been told he would be stabbed and would "lose four pints of blood". In September he had been forced to flee from the bus with friends after being threatened. One mother, who did not want to be named, said her 14-year-old son had been called "Jew boy" but begged her not to report the abuse because he was scared of reprisals.
Mr Miller said: "This was a nasty incident on a particular route and we hope there won't be more. We believe it is a particularly nasty group of individuals based in the West Hendon area [who are causing the problem].
"The school has worked with CST, TfL and the police to monitor it and the information I have suggests the interventions since last week have helped."
A CST spokesman said Jewish children suffering racist bullying while travelling to school was "a longstanding problem. It is sad but entirely understandable that some parents feel the need to take the precaution of children using private transport," he said.
A TfL spokeswoman said staff are working with police to investigate "antisemitic behaviour" on the route.
Det Insp Tony Caetano, of Barnet Police, confirmed officers had studied CCTV footage of the incident and are now carrying out a full investigation.
The Beatbullying charity this week published a major report into faith-based bullying. One in four children said they had been bullied because of their religion.