Montessori Culture (History): The Calendar

I had this printable with all the months of the year and it was fun for him to place the numbers in the right squares. 

We discussed how months may begin on different days. 
We also talked about how January ended on a Friday this year, so February began on a Saturday (the day after the last day in January). 
I mentioned the first day of the week and how it can be different in different countries. In the United States, for example, the first day of the week is Sunday, but in Mexico, it is Monday.
He put the days of the week in the correct order.
During the entire process, we consulted our calendar on the wall.