A group of youths, reportedly aged around 16, are said to have approached the five victims in the car park of the supermarket in Long Drive on Thursday evening (November 24).
The gang were said to demand the young boys' expensive jackets before one pulled a knife.
Speaking to getwestlondon, the mum of one of the victims said they had threatened to stab them.
The mum, who asked getwestlondon not to name her or her son, said: “There were lots of people walking past. It was brazen.
“They put their arms around their heads so it looked like they were their friends, but they said 'we're going to rob you blud.'
“They said if they talked they would go to their school and stab one of the boys.”
The victims are aged between 14 and 12 and were all kept off school on Friday (November 25) as a result.
It happened at around 7.30pm and reports of the terrifying ordeal surface on Friday morning.
The mum of the young victim said: “It makes my blood boil. Someone could have been stabbed last night.
“Last night he was very quiet. When he got up today he said he's not going out anymore.
“It's got to stop or something terrible will happen.”
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