The four-week campaign has been created by Facebook’s Creative Shop and aims to celebrate children’s imaginations.
The first video asks children to define a kronkiwongi and shows them building what they think is one out of Lego. There will be a further two videos released over the next two weeks.
The film was directed by MOD through RSA.
As part of the campaign Lego is encouraging parents to upload their children’s interpretations. Creative Shop and Lego will then create another video in the fourth week of the campaign showing the different kronkiwongis.
Lars Silberbauer, the director of global social media and search at Lego, said: "Our hope with this project is to inspire and engage parents all over the world, through an unscripted experience that sees children from different countries and cultures doing what they do best – using their creativity.
"There is no right or wrong when it comes to building a kronkiwongi. You can build a rocket and fly to the moon without even getting out from underneath the dining table, and parents everywhere witness these imaginative adventures every day."
The name kronkiwongi came from Silberbauer’s mother who used to challenge him to build a kronkiwongi out of Lego.
Rob Newlan, the head of Creative Shop, said: "The creative potential surrounding this project was unlimited, but our focus was to develop something that felt true to the Lego purpose and would resonate with parents on Facebook.
"And we’re incredibly proud of what we’ve created together; a series of videos that celebrate children’s unbridled imagination and creativity.
"Today, brands are under more pressure than ever to develop engaging, relevant content that can cut through online noise, which is why the endearing authenticity of these films is so powerful."