Marina del Rey is the beach destination that's closest to LAX. There you'll find things to do such as sightseeing, skating, biking, shopping and beach activities. Rental shops are located in Fisherman's Village, so you don't need to bring your own equipment.
Getting there: From LAX, a bus ride takes 15-30 minutes each way (including transfers). From the terminal at LAX, take Lot C Shuttle to LAX Transit Center. Proceed to Transit Dock #3 and take Santa Monica #3 to Lincoln Blvd / Minanao Way. The Visitor's Center is a short walk away, on the corner of Minanao Way and Admiralty. Fisherman's Village is within walking distance of the Visitor's Center. (Use MTA's Trip Planner to find the best route for your departure time.)
MTA's Metro Trip Planner displays schedules and fare information for LA metro buses and trains. It's fast and easy to use. Simply visit the MTA's website at Metro.net and you'll find the Metro Trip Planner on the top right side of the home page.
MTA's Metro Trip Planner
Time estimate: You will realistically need at least a 3 hour layover for this excursion. On planning for your return trip to LAX, don't forget to allow an additional hour to get through security and walking through the terminal at LAX.