My 7th grade students are in the middle of exploring fractions. They are currently researching the question:

**What are fractions and how can I add, subtract, multiply and divide them?**

I'm not sure how much instruction I want to give here. Is this intuitive? What can I do to make this more usable?

Applet with more instruction is here.

**Update**

John Golden:

@dcox21 @danielpearcy worth letting students adjust estimate afterfirst fraction is shown?

— John Golden (@mathhombre) November 8, 2012

Good idea. Updated version.