The youngster was one of 40 singers from Finchley Children's Music Group, who backed the pop legend during her headline performance in the London leg of the Live Earth extravaganza.
Sophie, who lives in Stoke Newington, said:
"It was really incredible. It went past in a flash because it was sort of mind-boggling, particularly with all those people shouting at you. It was a pretty insane experience, ridiculously exciting.
"But it was not very nerve-racking because of all the adrenaline. It's one of the best concerts I've done. I'm only 16 so it's a really crazy thing to do."
The troupe, around half of whom were from Haringey, backed the singer on Hey You, a song she penned especially for the concert.
Maddie Howe, 14, of Farrer Road, Hornsey, also a Channing School pupil, said: "It was one of the best experiences of my life. It was so fun - I want to do it again. The atmosphere was so vibrant.
"Madonna was really nice. She took time for each girl individually to talk about how they should do their hair. She said I want everyone's fringes up and we were like, OK."
Ben Turner, 11, of Hawthorn Avenue, Bounds Green, said: "My favourite part was standing on stage in the pitch dark and then the lights coming on and standing in front of 60,000 people. I had a lot of fun. Madonna was great."
Ben's mum Carolyn Gilbey, the group's administrator, revealed how a phone call out of the blue a month ago sparked an extraordinary journey into the limelight.
She said: "We're just a choir of ordinary school kids from north London more used to singing Mozart than Madonna. One day the phone rang and a voice said, 'Hi, I'm Angela, I'm Madonna's manager'."
The group beat off fierce competition from other choirs at auditions to land the once-in-a-lifetime chance to perform with the star.
From tottenhamjournal.co.uk.
Gratz Sophie! You got your own fansite! Oh well... this is Charlie Morris by the way, i was standing directly next to Madonna on the other side...
See you all at Summer School!