Some examples of systems diagrams created by children of various ages in the UK and Colombia. The children were prompted to think of something they wanted to achieve and to write that in the centre of the page...then to think of factors which influence their ability to achieve and write them on the page around the objective....then link the words with arrows showing the relationship....
Gimnasio Moderno Student Map. source 
Kalapa Bogota
Gimnasio Moderno Bogota
Go to Batuta Matata. source
Achieve strength
Achieve good grades
Hull Children's University
Achieve SATS depth
Learn english
Become a Photographer
Genwise India
Stop arguements
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