@hugoestr like web-mapping or hand-mapping? Because both angles probably have cool applications for HS students
(Or maybe not, I am neither cool nor a HS student so I'm probably way off base on my assumptions about both ;) )
@hugoestr anyway -- for web maps, I would say teach them a little bit about open data resources (e.g., if their local gov has a socrata portal, you can download spatial data from there), then turn them loose on Carto (see https://carto.com/learn/guides/intro/getting-started-with-carto-builder).
For handdrawn maps, maybe look into the kind of activities a number of Maptime chapters have done (e.g., http://maptimeatx.github.io/2015/02/26/hand-drawn-maps-recap/).
Hugo Estrada
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