**Volumes of Rotation Week!**

**Demos with Positive Impact**, build by David R. Hill and Lila F. Roberts. These are all demos that I have been using for YEARS now. They are absolutely wonderful, and the galleries include the functions in the examples – which makes them great for classroom examples. Start at the Visualizations for Volumes of Solids in Calculus page.

*x*-axis, and some around the

*y*-axis. I particularly like the 4-part construction of the washer-method problems (as shown in this picture below).

The shell method has got to be the toughest to visualize, and here’s where these demos are invaluable! Several real-life examples… nested Russian dolls, Angel Food cakes, Combos, toilet paper rolls, etc. are shown on the Shell Method Page and then (as always) there are a great collection of mathematical solids (4-part construction) in the Gallery.

If you just want to jump quickly to all the Galleries of Demos, go here.

Now, I don’t have a computer lab for my calculus class, but I have used these materials in several different ways from year to year: 1) Schedule time in a computer lab so that students can see each demo up close, 2) use a projection system, 3) have the students that have laptops bring the site up on their laptops. Almost all my calculus students have laptops now, so we essentially have a functioning “lab” if they all share their laptops.

**Possibly Related Posts:**

- Collection of Math Games
- Math Game: Antiderivative Block
- Playing to Learn Math (new version)
- Calculus Tweetwars: The End
- Calculus Tweetwars: 1676-1698