"Miss! We made it breathe out fire!" exclaimed 10-year-old Joe, pointing at the laptop on his desk, where he has programmed his animated dragon to belch flames into the face of the Greek hero Heracles.
Gasps of excitement ripple across the classroom, as the children at Launcelot school in south London try to work out the string of commands that Joe used to create their own virtual battles.
This is no special class -- it is a scene being recreated across England, which in September became the first major world economy to make coding a compulsory subject for children in publicly-funded schools from the age of five.
The government overhauled the computing curriculum after industry figures warned that children were not learning the skills they needed to compete in the 21st century.
And now these pupils are not just playing computer games, but learning how to make them.
Jemimah, a softly spoken 10-year-old in an immaculate blue and black uniform, smiles with satisfaction as she, too, manages to make her dragon breathe fire.
"At the first lesson I wasn't really sure how to do it. I had to have lots of help but I've been really getting it now," she says.
For many people, the word coding conjures up nightmarish images of lines and lines of text on a computer screen, written by hunched figures typing furiously.
But the students are using basic animation software that gives them a choice of command phrases -- move forward or back, lift a shield -- that can be arranged in sequence to make the brightly coloured characters come to life.
In another classroom, younger pupils are learning coding through an iPad programme called "Daisy the Dinosaur".
"It's fun because you get to tell them what to do," said six-year-old Ashley, as he swipes his finger to create a list of words such as "Spin" and "Jump" and then presses play to watch Daisy dance across the screen.
Six-year-old Feza is almost breathless as she demonstrates how to make Daisy "bigger, and bigger and bigger!"
"It has made the computer curriculum more exciting, engaging for the children. And it's not actually that difficult," said teacher Amy Riley.
"When you come down to it, it's a set of instructions."
- Using, not just consuming -
Britain has a fast-growing digital sector, from e-commerce to robotics and gaming, which accounts for about five percent of the country's growth, according to the "Tech City" industry organisation.
But like in many developed nations, the workforce is not keeping pace.
In a survey last year by research firm GfK, 45 percent of tech business leaders in London said a shortage of skilled workers is the biggest challenge they face.
The government has now replaced the old computing curriculum, with its focus on word processing and spreadsheets, with one that gives children an understanding of how computers work.
"In the 21st century, the ability to code and program a computer is no longer a nice-to-have, it's an essential," Finance Minister George Osborne said earlier this year.
Alex Hope, the managing director of leading British visual effects company Double Negative, has been outspoken on the need for Britain to improve the skills of its workforce.
"I think it's tremendous that coding is recognised as a vital skill, not just for the creative industries but for British industry in general," he told AFP.
His company won an Oscar for the effects in Hollywood movie "Inception" and currently employs more than 1,000 people worldwide working on other films, but has had to recruit many from overseas.
He highlights Israel as an example of how to teach coding in schools, but says all countries have to raise their game.
"If you want to be a developer of what computers can do, if you want to use them as a tool rather than a passive consumer of other people's technology, you need to be able to code yourselves," he said.
Although the government has allocated some funding for training, the teachers at Launcelot school taught themselves how to use the coding applications used in class.
And as the five-year-olds rapidly improve their skills, it will not be long before they know more than the staff.
"The children will take over -- they'll run with it," said headteacher Paul Hooper.