You have at least two fun options here, aside from turning on Netflix and slowly walking out of your TV room.
Round up the kids and take them out to the movies; be sure to buy popcorn for the bunch. Follow up with a trip to an ice cream parlor or your favourite pizza joint.
If your backyard can handle it, string up a white sheet for a movie screen and rent a projector to show your tween or teen's favourite movie. Have your guests bring sleeping bags so they can get comfy on the grass while watching the film. Provide some homemade popcorn and snacks to keep it festive