Mermaid Races
The pool is the perfect place to play mermaid games. Use water-safe treasures for the mermaids to dive for. You can use heavy plastic jewelry that will stay at the bottom of the pool, small toy fish or clams, weighted pool toys or real shells of different sizes. Put a couple clunkers in the mix such as an old boot and a tin can.
Use mono swim fins or mermaid fins available at swimwear supply stores. Get mermaid fins for each player or if that is not in your budget, tell them to swim with their legs together. Instruct the girls to swim down to find the treasures at the bottom of the sea (pool). For very young girls who may not have the swimming skills or for any non-swimmers, blindfold the participants and let them reach in a kiddie pool to find the treasures. Assign each treasure a point value. Add the treasure points each girl finds and the participant with the most points wins.
Run timed races for competitive swimmers wearing the mermaid or mono fins. Go from one side of the pool to the other or the full length of the pool. Start from the diving board, the side of the pool or from a standing position on the shallow end of the pool if the pool is too shallow for diving.
Mermaid Tea Party
Play a mermaid tea party game. Give each girl a plastic teacup to carry under the water. Use a stopwatch. Have all the girls go under the water at the same time or time them one by one. See how long each one can sit on or close to the bottom of the pool with her teacup. If the swimmers cannot get to the bottom of the pool, see how long they can dunk under the water. The tea party participant who can stay under the water the longest time is the winner.
Mermaid Memory
Place a variety of water- and mermaid-themed items on a large tray. Use 15 to 20 items such as a mermaid figurine, a small cut out mermaid tail made of fabric or paper, a tiny treasure chest, a pearl necklace, a starfish and different types of shells. Cover the tray with fabric or a towel before the girls see the items. Give each girl a piece of paper and a writing utensil. Uncover the tray of items. Hold each one up saying what it is. Set all the items back on the tray uncovered for about a minute so all the girls can look at the mermaid items one last time. Cover them up with the cloth. Give the girls one to three minutes to write down as many of the items as they can remember. The one who remembers the most wins the game.