Preschool Activity Calendars

In my classroom I like to organize the month using activity calendars. The calendars list 25 different activities/subject the kids will be working on throughout the month. I always send these calendars home so that parents have an idea about what their children are learning. One major omission from these calendars are the days of the week. I don't like to specify days of the week just in case we aren't able to get a certain activity. We all know that unplanned things pop up all the time, so I find it best not to include specifics.