Being the firstborn of two firstborns of two firstborns, my daughter often exhibits "type A" personality traits and one of those is planning and wanting to know what's going to happen. If you've read much on this blog, you will not be wondering where she gets it from, but trust me, it's from her father too. We're a hopeless cause, let me tell you!
Once she learned the days of the week (quickly followed by the months of the year), she started to understand more about time and the concept of days and weeks and months and she would ask me what was happening each day and when was it going to be ***day and what day was so-and-so coming, etc. Since she can't read yet, I decided to use the calendar in her room and pictures to help her understand when these things she was looking forward to were actually happening.
She loves being able to look at her calendar and she looks forward to each new month when we turn the page. I think it helps her to feel closer to family too since we live away from most of them so that she knows when they are having birthdays, etc.