Ruler grids have dark and light lines to show whole units and fractional parts. These grids make it easy to model operations with fractions, mixed numbers, and decimals. Students can trace and measure objects, or draw shapes with given dimensions. The following rectangle is a model for the product of 1-1/6 and 2-1/2 drawn on a grid with 6 parts per inch. (Download the FREE grid at the K-8 Math Sense TpT store.)

Ask students these questions about the model.

- What is the approximate area of the rectangle? [more than 2 square units, or about 3 square inches]
- What is the size of each small square? [1/36 square inch]
- How many small squares are in the rectangle? [7 x 15 = 105 squares]
- What are the dimensions as improper fractions in sixths [7/6 and 15/6]
- What is the area in thirty-sixths of inches? [105/36 or 2-33/36]
- What is the area in lowest terms? [35/12 or 2-11/12 square inches]