- The Well-Chosen Rectangle, a grid-paper approach to fraction arithmetic, presented in text, graphics, and video.
- Companion applets: Fraction Rectangles
Worksheets to make connections between fractions, angles, time, money, percents, and decimals — using the "pie slices" representation, including an applet to make your own pies.
The Egyptian Fractions Challenge — a great example of non-random practice and problem reversal.