In Calculus we just finished a project on volumes or revolution using disks and washers. I used a couple days or parts of days in class. I think it was worth the time in improved understanding.
Here is the assignment:
Doing this project helped me to see where students were still struggling to find the radius. Students had a hard time finding the radius when the region was between two curves and revolved around a line other than the x or y-axis. Doing this project gave them another reason to ask and help other classmates to find these expressions. Here are my class projects:
They used pancakes, cardboard, paper, foam, foam core, clay, cake, felt and pancakes. One group made a donut shape and passed out donuts in class to compliment their design.
One group even decked theirs out into a spaceship diorama with lights for stars.
Here are a few of my favorites.