As you can see in this example from September, students start out writing
very simple equations directly related to the calendar grid pocket chart
(butterflies, praying mantises, and beetles) and the magnetic tiles which
represent the number of days this month. Counting patterns and oral comments
have also been recorded.
September Number Corner
As students move through October, the equations become more complex and
sophisticated with the addition of money and the hundreds grid. After
November, students sometimes write equations on slips of paper and glue
them close to the appropriate calendar component. Students are encouraged
to make as many combinations possible in the time allotted.

October Number Corner
The paper calendar
components can also be offered to the students so they can color
them in and record equations independently. This gives
the teacher a good indication of how well each child understands the
group activity. The following examples are from May. On the left you
see a very able student’s work using One of the calendar components.
The range of his equation-writing abilities is clearly illustrated.
Next to his is a mid-ability student’s work. He chose to focus
on the hundreds grids that showed the 153rd day of school by writing
seven different equations. The student has developed multiple ways to
express 153 using One different models that make sense to him. He has
demonstrated that he understands odd/even numbers, patterns (colors on
the calendar) as well as equivalent expressions for 153, generated from
the 100 grid. This student has incorporated many different strategies
to demonstrate his numerical power and number sense. In this classroom,
Friday’s Figuring greatly improved students’ equation-writing
abilities, especially during problem-solving situations.

Student working with calendar components, Example 1

Student working with calendar components, Example 2