One of my favorite activities is to teach my field or research (network science) to high-schoolers. We (together with my colleague Cristina Brändle) have been doing that from our university to the local high schools in Madrid. Since they know concepts like equations, probability or geometry, it is somehow easy to show them concepts like what is a network, small world, friendship paradox or centrality. We usually have transparencies and allow them to work on Excel to perform some calculations which works well to understand the basic concepts of networks. At that level, there are a number of resources on the internet, including the Network Literacy Project lead by Mason Porter and collaborators, which also has some reflections about teaching Network Science to teenagers.
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