Do you think the story's ending is effective? Why or why not. the book is called "the open window"

This seems to be an opinion based answer. i think the best way to go about it would be to figure out what the theme/message is (friendship, unity, love) those are just examples it doesn’t have to be that then see if the ending does a good job at explaining the theme or ending the story in a way where the reader is satisfied with the events that have occurred (does the ending satisfy the events in the setup, confrontation, resolution)