Working in groups, the students examined the simulated impact of oil on a feather and how easy it is to wash off. One student in the group poured a mixture of vegetable oil and cocoa (added to give the appearance of darker crude oil) into a glass of water. The groups made observations of what happened to the oil such as, "The globs of oil went to the top."
Then I gave each student a seagull feather that I had collected from the Lake Michigan shore. The students dipped the feathers in a cup that had the oil and water mixture and made more observations:
"The feather gets heavier and skinnier," said one student.
"It got messy and oily," another added.
I encouraged them to imagine how the oil might affect a water bird. "It probably became so heavy that it couldn't fly or find food." Jose said.