In this goopy activity (page 2 of PDF under GPS: Glaciers Activity), learners will model glacial movement with “gak,” a white glue and liquid starch mixture. Each fist-sized gob of gak represents a year’s worth of snow, accumulating to form a “glacier” on a model landscape. Learners will record the gak’s rate of travel as well as make observations of other glacier behaviors. Relates to the linked video, DragonflyTV GPS: Glaciers.