The contest themed "Let's make our environment sustainable, together!" had four categories in the individual competition with over 7,000 paintings submitted from around the world.
Selen Arami, a seven-year old girl from Ahvaz city in southeast Iran, won the Planet Earth Grand Prix.
Fatemeh Abiri, a ten-year old girl from capital Tehran, received the Kao Prize and Kian Jamshidpoor, a ten-year old boy from Kermanshah, gained the Eco Friend Prize Jury's Special Prize.
All three children are members of the Center for the Intellectual Development of Child and Adolescent (CIDCA) which has branches in almost every Iranian city, offering children under 16 extra mental and cultural education.
Members of the center had submitted 34 painting works to the Kao contest and three of them were selected.
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