There are only a couple of things we know about the X Games. One is that this is the 12th year of BMX, moto, skateboard and other freestyle death-defying madness. The other thing is that mothers everywhere pray their sons will not aspire to any of it. This year’s big, five-day thrillathon takes place at both Staples Center and the Home Depot Center, so if you care about the difference between “BMX Freestyle Vert” and “BMX Freestyle Big Air,” you’ll need to do some research before you buy your tickets. Thurs.-Sun., Aug. 3-6; $5-$20; packages available. (213) 480-3232; www.expn.com.?