Access to the calendar (scheduler) is provided with the training menu items for convenience when dealing with training scheduling issues etc. In the image note the arrows.  Arrows appear when the calendar screen size is reduced by the user to the point where the calendar cannot display all the information for the day shown and the selected view.  In most cases this is because there is more than one task etc scheduled for that particular day. Click the drop down arrow to switch to day view and display all the day's tasks.

The calendar is also available from the Tools and New menu items.