May 20 Take Action Tour featuring Silverstein, Bayside, Polar Bear Club, The Swellers, Texas In July The Slowdown, 729 N. 14th St. 6:30 p.m., $17 Advance, $20 DOS, theslowdown.com, 402.345.7569 For 10 years, the Take Action Tour has been hauling bands across the nation for A Purpose. The Purpose that year is ever-changing — typically the recipient is a non-profit doing some fantastic advocacy work. And this year is no exception. They’ve eschewed any thought that it might be the Eagle Forum (right wing bands tend to be such bores) and this year they’ve gone for SEX, ETC., an organization dedicated to teaching responsible sexual health education to teens and people who have to deal with teens. And with shows like “Teen Mom” being watched by presumably thinking, breathing human beings, this is ever more important. So give like, four bucks a band to make sure that if teens are doing it (hint: a lot of them are), they’re at least doing it right.