Manhattan Beach is a great place to kill a few hours before or after a flight to/from LAX, but the following suggestion applies to pretty much all SoCal beaches. Try to find sand crabs if you don't mind getting your hands and feet wet. They are found in the intertidal zone. Bonus points if you build a sand castle with a moat and employ the sand crabs as castle security! https://www.youtube.com/watch?v=BmrYYF_DK-s