American Geosciences Institute
American Geosciences Institute: Earth Science Week: Exploring Porosity
Experiment to find out which size of gravel has the most porosity by measuring volume.
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Antarctic Geological Drilling: Environmental Literacy Framework Activities
An impressive collection of lessons on climate science and climate change. The entire book can be downloaded. As well, each lesson has its own page with some combination of background information, PowerPoints, images, maps, glossaries,...