I've visited on two different LA trips with my son, once when he was three and once when 7. At three he was blown away. At 7, he enjoyed it, but was a little past his car fascination stage, so he was less excited. There are a few good hands-on exhibits for kids, and a CHP motorcycle they can sit on. Adult car fans as well as movie and TV buffs will love it, too. Both times I've gone on weekdays it's been basically empty, and its convenient to the LA Farmer's Mkt, so good for a combined visit with that.
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