For my daughter's 5th birthday, we had a scavenger hunt! Upon arrival each child decorated a bag with markers including their name!  We have a big "common area" in our neighborhood that we used to place the "clues"...I found various "household" items from a clip art web site and had 81/2 X 11 color copies made of items such as a soccer ball, water ski, jump rope, red sweater, etc...I placed a sheet of paper (clue) at the first item indicating what they needed to look for and find next, then they had to look at the base of the tree or in the tree or on top of a swingset, etc...for the next item to receive the next clue. Each item found also had a goodie basket with it that contained small things that I found at the dollar store (necklaces, nail polish, candy, books, etc.)  We had about 20 clues and stops for everyone to go to. It was a fun time that took about 1 hour, they also had their goody bags ready to go. Topped it off with cake and ice cream and we had a terrific afternoon!