Google has recently added tasks to Google Calendar, after previously introducing the function as a Gmail Labs feature. Tasks will appear in the Tasks Gadget on the right side of your calendar grid. Using this feature, you can now assign due dates to your tasks that will appear on the “All Day” event section of Google Calendar.
You can create tasks either by clicking on an empty space in the “All Day” section or in Month view and then choose the task option. You can manage your tasks in the Tasks Gadget on the right side of your calendar. To mark a task as complete from within Calendar click on the checkbox next to the task. For more instructions on using tasks please click here