These are not Montessori Report Cards, but they are a good example of a basic report card on which you might base your own. Writing a report card is dependent on what you believe would be the most useful information for your parents or the next school to which your student will go.
A report card is usually a summary of work completed that year or that semester. Some Montessori schools simply offer a 5 sentence paragraph summary of activity with general comments. Some Montessori do not have any report card whatsoever. Some Montessori schools offer a checklist of several pages covering every activity that is presented in the class.
In the end, the decision to offer or not offer a report card will be based on to whom the information best serves.