This digital monthly calendar or planner for google slides is for the current school year. It includes free yearly updates. There is a slide for each month that includes a notes section along with showing the previous month and the upcoming month on the side. Most major holidays are already on the calendar but it is partially editable so you can add more. Textboxes have already been added but you can add more and customize to suit your needs.

This can also be used for team planning purposes. If you have multiple teachers teaching the same class you could use this as a calendar for the class or for daily prep. I typically add in events or duties that I have for the week at the top of the day.