This is a great twist on your basic scavenger hunt, and really easy to setup last minute as you do not have to write clues or even have the items set up for the players. It’s all “on the fly” creativity.
Print out enough game sheets for the teams playing. Split your guests into teams and give each team one game sheet and a pen or pencil. Have the teams select one person to be in charge of the game sheet and writing things down just to make things easier. Designate a time limit (30 minutes, or an hour if it’s a neighborhood range hunt) and set an area limit (“house and yard only”, or for a neighborhood hunt, “no further than Oak St” or “just on this block”.
Each team will try to make as many word items (actual objects – hat, nut, car) using the letters in “Halloween Scavenger Hunt” as they can. Then they must find the items represented by those words (eg. hat can be made using the noted letters, but card cannot because there is no “d”).
Teams score 1 point for each item word they can make, and they score 5 points for finding the item and bringing it back. At the end of the set time the team with the most points wins. You can also limit the points by only giving points to the word items made AND found, not just made.
Photo Hunt Option: If the players are old enough you can make it a photo hunt and allow the players to go around the neighborhood to find their items. Select one person per team to be the “photo keeper” and when they find their item they have to take a photo of it using their cellphone or digital camera (makes it easy to find “cars” or a “nest”). When the teams return (make sure to set the finish time a bit longer for a neighborhood search) they must show their photos to get credit for the items found.