I came up with this activity in response to the second grade Common Core Math Standard 2.G.A.2: Partition a rectangle into rows and columns of same-size squares and count to find the total number of them.

The rectangles on these four activity pages can be divided exactly into 1" rows and columns. Your students will use a ruler to mark the edges into inches, then joins the marks to create rows and columns. They will then count the squares to find the total number.

There are many sub-skills involved in this activity: holding the ruler still, measuring from 0, reading the measurement scale on the ruler, marking the inches accurately along the perimeter lines, and creating the columns and rows by drawing lines between the marks.

I've posted a free Powerpoint activity to introduce this activity to your students: Partition A Rectangle Into Same-Size Squares: Powerpoint.