More than 20 challengers met at St Matthew’s Primary School in Luton on Friday morning to cycle to Paris, raising money for Level Trust.
They were met at the school by Olympic champion Greg Whyte, who gave them a pep talk before they set off.
Professor Whyte OBE said: “It is a gargantuan challenge but they look like they are up for it.
“The children are in the background and it’s all for a fantastic cause. I am just here to set them off and make sure that they leave in the first place and wish them all the very best of luck!”
Pupils from St Matthew’s Primary cycled to school and made flags and banners and lined the streets to cheer the challengers off on their way.
Siobhan Rooney, of Pictons Solicitors, was one of the cyclists. She said: “It felt amazing to be waved off by hundreds of children flying flags and wishing us luck.
“The adrenaline rush it gave me made the first section of the ride seem much easier than I thought it would be.”
Luton Mayor, councillor Tahir Khan, Luton Town footballer Cameron McGeehan were also cheering at the start line.
The group cycled through London down to Brighton before taking the overnight ferry from Newhaven to Dieppe on the north coast of France.
From there they cycled to the French capital, arriving together at 6.30pm on Saturday.
Challenger Sing Li, of Machins Solicitors, said: “I am so proud that the team and I from Machins achieved this together with the other challengers.
“It was tough but we did it. It feels great.”
The event was organised by Daniel Coyle from Ryebridge Ltd raising money for local children’s charity, Level Trust.
Jane Malcolm, CEO of the charity, said: “Ryebridge are big supporters of ours. They have been incredibly generous in putting this event together for us. So far the challengers have raised a total of £8,457.50.
“The funding will go towards helping us provide school uniform, shoes and coats to children living below the poverty line in Luton.”