The Royal Mint is due to unveil the first UK coin designed by a child, which will enter circulation next year.
Florence Jackson, nine, from Bristol, beat 17,000 other entries to win a BBC One Blue Peter competition celebrating the 2012 Olympic Games in London.
Her high-jump motif is the first in a series of 29 officially-licensed 50p designs to commemorate the Olympics.
She said: "It was amazing to... see my picture turned into a coin. I can't wait to see it in my pocket money."
Her design, which will also feature the official London 2012 logo, will be revealed on Blue Peter on Tuesday.
Florence was joined by Olympic gold medallist Denise Lewis and Blue Peter presenter Andy Akinwolere to strike her first coin at the Royal Mint.
She said: "I'm so excited. It was a real surprise to win. I'd never entered a Blue Peter competition before, but really wanted to take part because I love drawing.
"I chose the high-jump because I'd watched it on TV before and thought it looked fun."
Ms Lewis said: "Florence has done all Olympians and Paralympians proud. Her design is simple and effective and I'm honoured to say I saw it first."
The remaining 28 designs for the special 50p coins will each depict a different Olympic or Paralympic sport.
The youngest person to have previously designed a UK coin was 26-year-old Matthew Dent from Bangor in Gwynedd last year.
Florence's winning design is the 17th to appear on the 50p.