Lisa Wainaina, aged 11, triumphed with her drawing called "The Day of the Child." As a reward, she received an upper case "G" of frosted glass, and her school won an interactive whiteboard.
"I thought I had a pretty secure job, but these kids are competition I wasn't aware of," Hwang joked. "My job security just went out the window."
Google held the competition to mark the launch of a new London office, which likeis called the Googleplex, on two floors of Belgrave House near Victoria Station.
Though Google has had a U.K. presence for the last seven years, the Googleplex marks an important point in the company's advance. According to executives at the launch, it will host a new engineering office and will function as a strategic center where the company will develop new ideas. It will also help Google continue expanding into Europe.
"Google is fast, aren't they?" said Nicky Gavron, deputy mayor of London. "They've already used London as the launch pad and set up in many European countries."
Omid Kordestani, vice president of business development and sales for Google, said the company is aiming to expand its global reach.
"Thirty percent of our revenues come from outside the U.S. My aim is to get it to the same level as our usage," Kordestani said.
Kordestani added that Google is particularly interested in benefiting from the U.K.'s wireless expertise, describing it as "light years ahead of the U.S."
Andrew Donoghue and Graeme Wearden of ZDNet UK reported from London.