The goal in this game is to compare two wholes, a blue bar and a red bar, which are unequal in size. At first, it's easy. The larger whole is always a multiple of the smaller. To compare them, you say something like:
2 red bars = 1 blue bar
Gradually, you work your way up until even this seems easy:
R = 5/2 B
The fractions factory provides all the tools and raw ingredients to build fractions. Starting with a whole, you can duplicate, divide, multiply, even multiply by a rational number to generate fractions of all sizes and 3 colors. Once you have mastered the basics, you can graduate to wholes of differing size.
The factory is wonderful for free exploration, but comes equipped with a sequence of instructions and multiple choices questions to get the ball rolling.