For years children were able to celebrate Halloween in the traditional way of going for house to house saying "Trick or Treat". Knowing that there would always be a treat. However times have changed, in many areas it is no longer to practice this tradition.
With the loss of one tradition, makes room for a new one. Well OK may be not new, but more common...

The Halloween Party! Here's some cool ideas to decorate your room!
Let's create the cutest atmosphere of an Haunted Room, a great place to sleep if you are brave enough to be having a slumber party.
Cover windows with blankets, garbage bags or foil to block light.
Remove breakables!!!!!

Cover furniture with cheap black fabric. This serves two purposes: one it looks cool and most important it protects the furniture!

Floating Ghosts - Cover helium filled balloons with pieces of white cloth. Old sheets are great! Draw eyes with black marker. You can also do ghosts by simply using white balloons and drawing the face directly on them. Use little pumpkins for weights.

Wax Paper Ghosts - Pull off a large piece of wax paper, bunch up into a ball. Tear off two to three more pieces, drape over first piece, tie with string, yarn, rubber band... under ball. This will make the head. Draw eyes with black marker. Hang from ceiling with fishing line.

Spider Webs - Pull cotton batting apart and drape across furniture and hang in door ways. Attach little plastic spiders.

Fog - Place dry ice in a container of warm water. Rectangle flower boxed are great, because of their shape and size. Simply set on floor next to the wall. Warning keep small children away from ice.