My children learned about the days of the week and the
months of the year by making calendars. We also took note of the day every
morning. When it is Monday, tell them that today is Monday and yesterday
was Sunday and tomorrow is Tuesday. It may take a while before your child
fully understands and remembers the days and what yesterday and tomorrow
mean. Talking about it each day [briefly!] will help them a great deal.
Once they have a general understanding of what a month is and when they are old enough, have them create a calendar using a blank calendar template. The templates at donnyoung.org are linked on the right. Since this was my pre-windows-computer days with its fancy programs, I drew the templates myself. An older child could draw the template.
The calendar pictured here was made by my daughter [first grade]. It features Sonic, Tails, Knuckles, and Sally.
While they are doing this, have them make two consecutive [or three] months in one sitting to show them that where a month ends, the following month begins on the next day. That seems like a no-brainer, but show it to them anyway or see if they can grasp this on their own.
Planner Related
This is a photograph showing where I noted the calendar assignment, or perhaps the completion of the assignment. I placed it in the language arts category
Teaching How Many Days for Each of the Months
Time Concepts Series: Calendars, Grades 4-6
Color Sonic 