The 16 finalists, from sixth forms and colleges across London, spent a week at the London College of Fashion during the summer holidays, honing their designs in preparation for the show.
April Griffiths, 17, from Brooke House sixth-form college in Clapton, east London, won the chance to join the design team at George at Asda for a two-week placement later this year, and see her outfit produced and sold in the stores.
The teenager impressed judges in a competition run by Fashion Awareness Direct, which also ran the workshop, with her stylish take on a traditional sports outfit.
She created her own tracksuit with ribbing around the jacket bodice and bell-shaped sleeves.
April, who is studying for a Btec national diploma in art and design and taking AS level psychology, said: "Just to make an outfit on my own and see it on a catwalk was amazing."
She said she would like to pursue a career in fashion and study the subject at university. "Ever since I saw my first fashion show when I was 12, I've wanted to be a fashion designer. I can't wait for the placement."