Do you use Arrays in the math class? We do! With arrays, you are able to accomplish so much:
label fractional parts
Create Equivalent fractions with scale factor
Model the fractional parts
Compute the four basic operations
By the time I get the kids in 8th grade, we review over the arrays, but they are already familiar with them. I do not make the kids model every time they do a fraction computation, but it is a tool in their toolbelt. Some of the kids do model each time because they see it that way. Fractions are tough! Modeling with arrays offer so much.
You can model with arrays with graph paper or you could use the color tiles. In 8th grade, I focus on graph paper.
The most difficult fraction computation is division! We do not teach the short cut of "keep it, change it, flip it!" We teach them how to divide the fractions. The arrays do allow for a model to be created in which the kids get a better understanding as to what division of fractions means. When you teach the shortcut, the understanding is lost!