Tired of the same old kids' birthday party ideas? Try a mystery party in which kids have to figure out riddles, follow clues or find hidden items to complete a mystery and win prizes. Take things up a notch from the standard scavenger hunt by having party guests complete tasks, answer riddles and solve a mystery tied in with the party theme, based on a familiar mystery or a story you create yourself. Develop your clues based on the party-goers' ages, reasoning skills and reading ability.
Cut shapes that tie in with the party's theme from colored card stock. For a mystery set on the farm, you might cut shapes of familiar farm animals or implements. The clues for a pirate mystery might be on cutouts of items such as a treasure chest, a sailing ship and a parrot. Cut a shape for each clue the kids must use to solve the mystery.
Draw or print each clue on one of the shaped cutouts. Use simple words or visual clues for younger children so they can readily understand them. Older kids might enjoy clues written as riddles or anagrams of the key words to make solving them more challenging. Clues must also incorporate hints or actual instructions to guide kids to subsequent clues. Number the clues in the order kids need to use them to solve the mystery.
Craft each clue to clearly identify an item the kids need to find or a key element of the mystery story. "Your next clue is in a body of water where feathered creatures swim" could direct kids to find something in an outdoor bird bath, for example. Keep it simple for younger children or non-readers: a drawing of a mailbox with a question mark on it would indicate their next clue is in the mailbox out front. The mystery item -- perhaps a pair of glasses -- found in the birdbath or mailbox would include a note to help kids solve the mystery: a note attached to the glasses stating "the thief did not wear these" tells kids to rule out any suspects with glasses.
Arrange the clues around your house or yard so the kids can spread out to find them. If you've hidden just one set of clues, remind each child or team of kids not to take or move the clues as they come across them, to be fair to other participants. Instead, give each team a notebook to jot down the information from each clue or hint they find. As an alternative, make duplicate sets of clues, each set on a different color card stock, and allow team members to collect their team's colored clues as they go. Set up the clues around the party area in spots that are somewhat hidden from view but in safe locations for children to access.