Some activities you can do with a pool noodle include playing water balloon baseball and playing giant tic-tac-toe. Another pool noodle activity is to make a marble racetrack.
To play water balloon baseball, insert a dowel securely into the middle of a length of pool noodle to make a "bat." Fill several water balloons about halfway full with water and use them like baseballs.
To play giant tic-tac-toe, use four noodles to make a tic-tac-toe board. One player stands on each side and takes turns tossing bean bags into the spaces. The first player to get three in a row wins.
Make a marble racetrack by cutting a pool noodle in half and using toothpicks to secure the halves side-by-side. Place the tracks on an incline and see whose marble can reach the finish line first.