Read this paragraph. The students crowded in closely to hear their museum guide’s explanation. As she spoke she pointed to various features of the engineering exhibit, and soon the students were invited to explore. One group compared arched bridges to cantilevered bridges, and then they designed their own virtual bridges. Other students built mini electric circuits and illuminated light bulbs. And an aerospace group tinkered with paper airplane design, launching their models from a mini airstrip on the second-floor balcony. What do the descriptive details reveal?.